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Results of Norwood stage I operation: Comparison of hypoplastic left heart syndrome with other malformations
Abstract
We compared the Norwood stage I operation for hypoplastic left heart syndrome and other complex malformations with ductus-dependent systemic circulation.
A retrospective study of 194 patients who underwent a Norwood stage I palliation between 1990 and 1998 was conducted. Malformations in 131 patients were classified as hypoplastic left heart syndrome, defined as aortic and mitral atresia or severe stenosis, normal segmental anatomy, intact ventricular septum, and hypoplasia of the left ventricle. Sixty three patients had other lesions: hypoplastic left ventricle with ventricular septal defect (n = 18), unbalanced complete atrioventricular canal (n = 9), complex double-outlet right ventricle (n = 14), double-inlet left ventricle (n = 11), tricuspid atresia with transposition of the great arteries (n = 6), and others (n = 5), including heterotaxia.
Operative (>30 days) and 1-year survivals were lower for patients with hypoplastic left heart syndrome than for those with other lesions (63.4% vs 81%, P =.008, and 51.2% vs 71.4%, P =.02, respectively). The presence of a nonhypoplastic left ventricle (n = 27) was associated with higher operative and 1-year survivals (96.3% vs 64.7%, P =.002; 88.9% vs 52. 7%, P <.001). A restrictive atrial septal defect and prematurity tended to increase mortality across both groups. Cox proportional hazards regression indicated that a single right ventricle was the most important independent predictor of death (P <.001). Operative mortality for all patients undergoing the stage I procedure decreased from 38.5% (1990-1994) to 21.4% after 1994 (P =.02).
The survival of patients with malformations other than hypoplastic left heart syndrome after the Norwood procedure is greater than for those with hypoplastic left heart syndrome. Staged palliation is valid surgical therapy in these patients, with good results in intermediate follow-up.
... Some other malformations may present with the same physiology as HLHS, such as double-inlet left ventricle (DILV), tricuspid atresia with transposition, unbalanced atrioventricular septal defect (AVSD), and some complex forms of double-outlet right ventricle (DORV) with left ventricular outflow tract obstruction (LVOTO) [1,5,6,[9][10][11]13]. An association often exists between hypoplasia of the aortic arch and coarctation or interrupted aortic arch. ...
... The patients who undergo the modified Norwood pathway may have better results than the patients with typical HLHS due to the presence of a morphologic left ventricle (LV) [1]. This study aimed to compare the outcomes of the modified Norwood procedure for these two groups at a single center. ...
... a Hypoplastic left heart syndrome (HLHS) group. b Non-HLHS group Daebritz et al. [1] compared the outcomes between typical HLHS and other malformations with the same pathophysiology and found a greater operative and 1-year survival in the non-HLHS patients. These authors hypothesized that a morphologic left systemic ventricle was contributing to a higher survival rate in the non-HLHS group. ...
Recent studies have suggested that survival after the modified Norwood procedure is influenced by anatomy and is worse for patients with hypoplastic left heart syndrome (HLHS) than for patients with other forms of functional single ventricle. This study aimed to compare the outcomes of the modified Norwood procedure for these two groups at a single center. A retrospective chart review compared modified Norwood procedure outcomes between children with HLHS (n = 40) and children with other single-ventricle malformations (n = 19) from January 2002 to August 2012. The HLHS patients had a lower mean age (10.0 ± 13.2 days) at the time of operation than the non-HLHS patients (16.5 ± 18.5 days). The difference was not significant. The number of patients with a Sano modification was significantly higher in the HLHS group (HLHS 85 % vs non-HLHS 32 %; p
... CHD with SV physiology encompasses a group of severe abnormalities in the cardiac structure, characterized by underdevelopment of one side of the heart, resulting in a univentricular circulation. SV patients have a higher risk of mortality than patients with any other CHD and patients with a systemic right ventricle (RV) in particular, such as those with hypoplastic left heart syndrome (HLHS), represent the most common SV sub-type and tend to have worse outcomes [2][3][4][5][6][7][8][9][10][11]. However, while survival of SV has improved, progressive ventricular dysfunction and ultimate heart failure remain both a common cause of death and indication for cardiac transplantation in this population [12][13][14][15]. ...
... Because the adaptations of the RV are not tailored to support the high-pressure systemic circulation, patients with SV of RV morphology are at particularly increased risk of morbidity and mortality [2][3][4][5][6][7][8][9][10][11] and may be uniquely vulnerable to metabolic changes in energy generation and utilization. In fact, patients with SV have significantly decreased exercise tolerance [21], further suggesting their inability to modulate metabolic demand appropriately. ...
There are growing numbers of infants and children living with single-ventricle congenital heart disease (SV). However, cardiac dysfunction and, ultimately, heart failure (HF) are common in the SV population and the ability to predict the progression to HF in SV patients has been limited, primarily due to an incomplete understanding of the disease pathogenesis. Here, we tested the hypothesis that non-invasive circulating metabolomic profiles can serve as novel biomarkers in the SV population. We performed systematic metabolomic and pathway analyses on a subset of pediatric SV non-failing (SVNF) and failing (SVHF) serum samples, compared with samples from biventricular non-failing (BVNF) controls. We determined that serum metabolite panels were sufficient to discriminate SVHF subjects from BVNF subjects, as well as SVHF subjects from SVNF subjects. Many of the identified significantly dysregulated metabolites were amino acids, energetic intermediates and nucleotides. Specifically, we identified pyruvate, palmitoylcarnitine, 2-oxoglutarate and GTP as promising circulating biomarkers that could be used for SV risk stratification, monitoring response to therapy and even as novel targets of therapeutic intervention in a population with few other options.
... There is mixed evidence in regards to differences in outcomes between patients undergoing a Norwood for non-HLHS versus HLHS anatomy. Some authors have found that the non-HLHS cohort has lower rates of mortality and re-intervention, while others have found no difference [6][7][8]. Consistently, significant heterogeneity has been noted in the non-HLHS population undergoing Norwood operations. The purpose of this study was to compare survival and neurodevelopmental outcomes between patients with HLHS vs non-HLHS anatomy, in a large well-described population of consecutive single ventricle patients requiring a Norwood procedure at a single center. ...
... The association between anatomy and post-Norwood survival has been assessed in several previous papers over the last two decades. Initial reports suggested that HLHS anatomy was a predictor of poor survival [6,7], but subsequent studies have since demonstrated that non-HLHS anatomy is not predictive of improved outcomes [8,22]. This perhaps represents an evolution in surgical technique and peri-operative management, though it is difficult to delineate the exact factors. ...
There is evidence to suggest that patients undergoing a Norwood for non-HLHS anatomy may have lower mortality than classic HLHS, but differences in neurodevelopmental outcome have not been assessed. Our objective was to compare survival and neurodevelopmental outcome during the same surgical era in a large, well-described cohort. All subjects who underwent a Norwood–Sano operation between 2005 and 2014 were included. Follow-up clinical, neurological, and developmental data were obtained from the Western Canadian Complex Pediatric Therapies Follow-up Program database. Developmental outcomes were assessed at 2 years of age using the Bayley Scales of Infant and Toddler Development (Bayley-III). Survival was assessed using Kaplan–Meier analysis. Baseline characteristics, survival, and neurodevelopmental outcomes were compared between those with HLHS and those with non-HLHS anatomy (non-HLHS). The study comprised 126 infants (75 male), 87 of whom had HLHS. Five-year survival was the same for subjects with HLHS and those with non-HLHS (HLHS 71.8%, non-HLHS 76.9%; p = 0.592). Ninety-three patients underwent neurodevelopmental assessment including Bayley-III scores. The overall mean cognitive composite score was 91.5 (SD 14.6), language score was 86.6 (SD 16.7) and overall mean motor composite score was 85.8 (SD 14.5); being lower than the American normative population mean score of 100 (SD 15) for each (p-value for each comparison, <0.0001). None of the cognitive, language, or motor scores differed between those with HLHS and non-HLHS (all p > 0.05). In the generalized linear models, dominant right ventricle anatomy (present in 117 (93%) of patients) was predictive of lower language and motor scores. Comparative analysis of the HLHS and non-HLHS groups undergoing single ventricle palliation including a Norwood–Sano, during the same era, showed comparable 2-year survival and neurodevelopmental outcomes.
... It is important to recognise that our study included HLHS variants as well as other anatomical morphologies treated with the Norwood procedure. Although studies have demonstrated no difference in early survival comparing HLHS with non-HLHS morphologies [8,9], Daebritz et al. [10] demonstrated a lower 30-day and 1-year mortality with cardiac malformations other than HLHS. The NZ experience is more in line with the findings of Daebritz et al., in that small-sized ascending aorta followed by the absence of antegrade aortic blood flow and a systemic RV were more strongly associated with early death. ...
... 10). An antenatal diagnosis of a major structural cardiac anomaly was made by fetal echocardiography in 88% of the patients. ...
Background:
Babies born with a functional single ventricle heart and systemic outflow tract obstruction may require a Norwood (NW) procedure as the first of three staged procedures to obtain a Fontan circulation. This procedure and the following treatment pathway are associated with significant mortality. Risk factors for the Norwood procedure and the subsequent pathway are not necessarily the same. To identify these factors within New Zealand, the collective experience with the Norwood procedure was examined.
Methods:
Charts from 133 New Zealand children undergoing Norwood procedure from 1992 to 2014 were examined. Deaths were assigned as "early" (30-day or in-hospital) or "late" (based on timeframe from the Norwood procedure). Cardiac anatomic, patient demographic and surgery related variables were examined. Important risk factors were identified using univariate and multivariate analysis. Kaplan-Meier survival curves were calculated.
Results:
Survival following the Norwood procedure was 83%. Overall survival was 67% at six months, 65% at one year, and 63% at five years. Size of the ascending aorta appeared as an important risk factor with "early" death while New Zealand deprivation index and low birth weight appeared more important for "late" death. These factors each impacted overall survival.
Conclusions:
The Norwood procedure and subsequent medical treatment carries significant mortality in New Zealand. Cardiac anatomical factors affect survival of the immediate Norwood procedure whereas social factors weigh more significantly on longer term survival. Nevertheless, both anatomical and social factors carry real survival risk.
... The interval between the Norwood procedure and the next surgical stage of repair (i.e., Glenn or hemi-Fontan procedures) remains a vulnerable period for potential catastrophic events with an inter-stage mortality of approximately 15% and as high as 30%. [120][121][122] Multiple etiologies of mortality include myocardial ischemia from coronary artery impairment, neo-aortic obstruction, restrictive ASD, shunt stenosis or thrombosis, right heart dysfunction, arrhythmias, intolerance to dehydration and respiratory infections, and pulmonary and systemic circulation imbalance with ensuing organ failure or hypoxemia. [122][123] If the patient presents to the ED during this peri-od with SpO 2 less than 75%, it is reasonable to provide supplemental O 2 and fluid resuscitation. ...
... [120][121][122] Multiple etiologies of mortality include myocardial ischemia from coronary artery impairment, neo-aortic obstruction, restrictive ASD, shunt stenosis or thrombosis, right heart dysfunction, arrhythmias, intolerance to dehydration and respiratory infections, and pulmonary and systemic circulation imbalance with ensuing organ failure or hypoxemia. [122][123] If the patient presents to the ED during this peri-od with SpO 2 less than 75%, it is reasonable to provide supplemental O 2 and fluid resuscitation. It is important to identify the cause of the SpO 2 desaturation. ...
... Prematurity is a risk factor for operative mortality as reported by Daebritz et al. [18]. This observation may be associated with age (maturity of the child), but there is no consensus of opinion that this factor can affect short-term survival [19,20]. ...
Background
Hypoplastic left heart syndrome is a lethal congenital heart malformation when untreated resulting in a 95% mortality in the first month of life. In this study, we aimed to investigate the newly introduced inflammatory biomarker, neutrophil–lymphocyte ratio, as a mortality predictor in postoperative hypoplastic left heart syndrome patients.
Methods
Patients were divided into two groups; Group 1 consisted of 33 patients who were discharged and Group 2 including 20 patients who were deceased following surgery. Patients’ preoperative demographic characteristics, total white blood cell counts, neutrophil counts, lymphocyte counts, neutrophil–lymphocyte ratio, C-reactive proteins, alanine aminotransferase, aspartate transaminase, urea, and creatinine levels were recorded. Studys’ primary endpoint was all-cause patient mortality following surgery.
Results
The preoperative neutrophil–lymphocyte ratio was found to be significantly different between the groups (p = 0.001). High neutrophil–lymphocyte ratio was found to be associated with an increased risk of death. The ROC curves of neutrophil–lymphocyte ratio were found to be associated with mortality. The area under curve for the preoperative neutrophil–lymphocyte ratio was 0.74. Neutrophil–lymphocyte ratio predicted mortality with a sensitivity of 78% and a specificity of 65%.
Conclusion
Neutrophil–lymphocyte ratio can contribute to the early identification of patients at high risk for complications. In addition, through the use of NLR, clinicians could implement measures for the optimal therapeutic approach of cardiac surgery patients and the elimination of adverse patient outcomes.
... In our study findings revealed overall survival rate of 79% which is higher than that reported by Silverman and his colleagues, but he reported maximum survival prenatal rate 100% which was higher compared to what our stay finding 74%. Regarding postnatal survival rate, our study revealed higher rate 81% than the reported rate by Leval et al. [15], 57% , Jonas et al. [32] , 64%; 51%; and Atallah et al. [33], 71% respectively. ...
Introduction: Diagnosis of congenital heart diseases including Hypoplastic Left Heart Syndrome (HLHS) in prenatal becomes a routine practice. It allows better preoperative management and offer opportunity to parents and physicians to intervene earlier. We described differences in survival outcome for patients diagnosed prenatal or postnatal period with HLHS in and who had surgical intervention study area.
Methods: Survival analysis using Kaplan-Meier product limit method was performed to estimated probability of survival for 88 patients diagnosed with HLHS and surgical intervention. The primary outcome measures were 12 months survival after birth and after surgical intervention.
Results: Overall one year survival for HLHS patients was 63%. There was difference in survival between the two study groups (65% vs. 60%) for postnatal and prenatal diagnosis of HLHS respectively. This difference was not statistically significant (P=0.4). On the other hand, there was variation in survival according to intervention (80% vs. 0%) for patient who underwent surgery and those who declined surgery correspondingly. The difference was statistically significant (P<0.0001). However, there was no statistically significant difference in survival between prenatal and postnatal diagnosis of HLHS after surgery (67% vs. 63%; P=0.7%) respectively.
Conclusion: In this study surgical intervention increases survival for patients diagnosed with HLHS, but there was significant difference in survival between prenatal or postnatal diagnosis of HLHS. Further studies of large sample size are prerequisite to investigate survival outcomes in Hypoplastic Left Heart Syndrome.
... 2,3 Although the SV heart disease can be a morphological right ventricle (RV), left ventricle, or of indeterminate morphology, single RV lesions such as hypoplastic left heart syndrome may be inherently at risk for heart failure (HF) presumably because of inherent limitations in the RV's ability to tolerate increased afterload. [3][4][5][6] As such, eventual HF is a leading cause of death and indication for heart transplant in the SV heart disease population. 3 Although surgical techniques and perioperative care for SV heart disease continue to improve, long-term survival and quality of life ultimately depend on preservation of RV function. ...
Background
Single ventricle (SV) congenital heart disease is fatal without intervention, and eventual heart failure is a major cause of morbidity and mortality. Although there are no proven medical therapies for the treatment or prevention of heart failure in the SV heart disease population, phosphodiesterase-5 inhibitors (PDE5i), such as sildenafil, are increasingly used. Although the pulmonary vasculature is the primary target of PDE5i therapy in patients with SV heart disease, the effects of PDE5i on the SV heart disease myocardium remain largely unknown. We sought to determine PDE5 expression and activity in the single right ventricle of SV heart disease patients relative to nonfailing controls and to determine whether PDE5 impacts cardiomyocyte remodeling using a novel serum-based in vitro model.
Methods and Results
PDE5 expression (n=9 nonfailing; n=7 SV heart disease), activity (n=8 nonfailing; n=9 SV heart disease), and localization (n=3 SV heart disease) were determined in explanted human right ventricle myocardium. PDE5 is expressed in SV heart disease cardiomyocytes, and PDE5 protein expression and activity are increased in SV heart disease right ventricle compared with nonfailing right ventricle. Isolated neonatal rat ventricular myocytes were treated for 72 hours with nonfailing or SV heart disease patient serum±sildenafil. Reverse transcription quantitative polymerase chain reaction (n=5 nonfailing; n=12 SV heart disease) and RNA sequencing (n=3 nonfailing; n=3 SV heart disease) were performed on serum-treated neonatal rat ventricular myocytes and demonstrated that treatment with SV heart disease sera results in pathological gene expression changes that are attenuated with PDE5i.
Conclusions
PDE5 is increased in failing SV heart disease myocardium, and pathological gene expression changes in SV heart disease serum-treated neonatal rat ventricular myocytes are abrogated by PDE5i. These results suggest that PDE5 represents an intriguing myocardial therapeutic target in this population.
... In early studies, the AAMA cohort had a higher mortality rate, likely related to the diminutive size of the ascending aorta and its effect on coronary perfusion. 20,21 More recent studies have suggested that the AAMS group has a higher mortality; it has been surmised that this finding is related to the presence of coronary cameral fistulous connections in patients with this anatomic subtype of HLHS. [22][23][24] However, the SVR trial and other studies did not find anatomic subtype as a risk factor for mortality. ...
Background:
Children with single-right ventricle anomalies such as hypoplastic left heart syndrome (HLHS) have left ventricles of variable size and function. The impact of the left ventricle on the performance of the right ventricle and on survival remains unclear. The aim of this study was to identify whether left ventricular (LV) size and function influence right ventricular (RV) function and clinical outcome after staged palliation for single-right ventricle anomalies.
Methods:
In the Single Ventricle Reconstruction trial, echocardiography-derived measures of LV size and function were compared with measures of RV systolic and diastolic function, tricuspid regurgitation, and outcomes (death and/or heart transplantation) at baseline (preoperatively), early after Norwood palliation, before stage 2 palliation, and at 14 months of age.
Results:
Of the 522 subjects who met the study inclusion criteria, 381 (73%) had measurable left ventricles. The HLHS subtype of aortic atresia/mitral atresia was significantly less likely to have a measurable left ventricle (41%) compared with the other HLHS subtypes: aortic stenosis/mitral stenosis (100%), aortic atresia/mitral stenosis (96%), and those without HLHS (83%). RV end-diastolic and end-systolic volumes were significantly larger, while diastolic indices suggested better diastolic properties in those subjects with no left ventricles compared with those with measurable left ventricles. However, RV ejection fraction was not different on the basis of LV size and function after staged palliation. Moreover, there was no difference in transplantation-free survival to Norwood discharge, through the interstage period, or at 14 months of age between those subjects who had measurable left ventricles compared with those who did not.
Conclusions:
LV size varies by anatomic subtype in infants with single-right ventricle anomalies. Although indices of RV size and diastolic function were influenced by the presence of a left ventricle, there was no difference in RV systolic function or transplantation-free survival on the basis of LV measures.
... The availability of data was also variable. Patients were not managed with a standardized approach, and therefore, we could not make an early decision on the timing of the second-stage operation in patients with risk factors reported previously [16][17][18][19], such as low birth weight, prematurity, septic condition, small ascending aorta, atrioventricular valve regurgitation of more than moderate grade, pulmonary congestion because of a restrictive foramen ovale, and dysfunction of the systemic ventricle. ...
... Prematurity is a risk factor for operative mortality as reported by Daebritz et al. [18]. This observation may be associated with age (maturity of the child), but there is no consensus of opinion that this factor can affect short-term survival [19,20]. ...
... In a patient with hypoplastic left heart syndrome, a search pattern should include evaluation for alternative decompressive pathways. Patients in the subgroup of with hypoplastic left heart with restricted interatrial septal defect or intact interatrial septum are more likely to have other decompressive pathways and also have a poorer surgical outcome [13,14]. Early relief of left atrial hypertension is of paramount importance. ...
This article focuses on the embryology, hemodynamics, and CT and MRI features of levoatriocardinal vein. Levoatriocardinal vein, a form of pulmonary systemic connection, is most commonly seen in left heart obstructive lesions, providing an alternative egress for pulmonary venous blood.
Levoatriocardinal vein can be differentiated from other more common anomalies, such as anomalous pulmonary venous return, persistent left superior vena cava, and dilated left superior intercostal vein, by its distinctive imaging features.
... Some variables have been shown as risk factors for mortality before the BDG procedure. Low body weight, prematurity, preoperative shock, small ascending aorta, significant tricuspid regurgitation and extracardiac abnormalities are poor prognostic factors for survival, as shown previously [18][19][20][21][22]. In our study, prematurity, low birth weight, circumference and the age at the bPAB procedure were not significantly associated with mortality. ...
OBJECTIVES Bilateral pulmonary artery banding is considered as ‘first-stage’ palliation for neonates who have hypoplastic left heart
syndrome. This study aimed to identify risk factors that influence outcome before the bidirectional Glenn operation.
... The ensuing decades saw the use of the MBTS as the favored source of pulmonary blood flow [16][17][18][19][20][21]. Although first proposed by Norwood, the first report in the current era of the use of an RVPAS was by Kishimoto and colleagues from Osaka, Japan [22][23][24][25]. ...
Hypoplastic left heart syndrome, the most common complex congenital heart malformation, is characterized by underdeveloped left-sided heart structures. The Norwood procedure followed by two-staged operations has permitted the extended survival of many of these patients. Survival, however, remains suboptimal with most of the morbidity and mortality occurring during the Norwood procedure hospitalization. The modified Blalock-Taussig shunt has been implicated in contributing to the mortality risk due to decreased systemic diastolic blood pressure and coronary perfusion. Therefore, the right ventricle-to-pulmonary artery shunt was recently reevaluated as a lower-risk source of pulmonary blood flow in the Norwood procedure. The Pediatric Heart Network Single Ventricle Reconstruction trial, sponsored by the NIH National Heart, Lung and Blood Institute, evaluated the two types of shunts during the Norwood procedure. This randomized clinical trial has yielded important insight into the effects of shunt selection on morbidity, mortality, hemodynamics and overall current outcomes for hypoplastic left heart syndrome.
... As publicações demonstravam O grupo do Children's Hospital, de Boston, fez um estudo comparando os resultados do primeiro estágio da operação de Norwood em SHCE com o mesmo procedimento aplicado a outras malformações. Esse grupo demonstrou que a sobrevida operatória e em um ano na presença de ventrículo esquerdo não-hipoplásico (respectivamente de 96,3% e 88,9%) foi significantemente melhor que as sobrevidas na SHCE (64,7% operatória e de 52,7% em um ano) 13 . ...
OBJECTIVES: To report a surgical strategy for the Norwood procedure in the hypoplastic left heart syndrome (HLHS) that enables short hypothermic circulatory arrest time and aortic arch reconstruction with autologous pericardium patch, and to compare the results of the modified Blalock-Taussig (mBT) shunt with the right ventricle-to-pulmonary artery (RV-PA) conduit procedures as the source of pulmonary blood flow. METHODS: Retrospective study of 71 newborns with HLHS consecutively operated between March, 1999 and February, 2006. One technique for reconstruction of the neoaorta and two different techniques for reestablishment of the pulmonary blood flow were used: the mBT shunt in the first 37 newborns and RV-PA conduit in the last 34. Cannulation of the ductus arteriosus for arterial perfusion was the main part of the surgical strategy to reduce the hypothermic circulatory arrest time. RESULTS: In-hospital survival for the entire cohort was 74.64%, or 67.57% and 82.35% for the mBT shunt and RV-PA conduit groups, respectively (p=0.1808). Mortality rates between the first and second palliation stages were 40% and 4.4% for the mBT shunt and RV-PA conduit groups, respectively (p=0.0054). Hypothermic circulatory arrest times were 45.79±1.99 min and 36.62±1.62min (p=0.0012), respectively. Late coarctation of the aorta occurred in five patients (7.2%). CONCLUSION: This surgical strategy resulted in short circulatory arrest time, low mortality and favorable morphology of the neoaorta, with low incidence of late coarctation of the aorta. The higher rate of survival to first palliation stage with the RV-PA conduit was not significant, but interstage mortality was statistically lower when compared with the modified Blalock-Taussig shunt procedure.
... Such patients are uniformly treated using single-ventricle palliation algorithms, and outcomes in this subset of uAVSD are well documented. [13][14][15] As it is more readily appreciated echocardiographically, ventricular hypoplasia dominates the diagnostic milieu of uAVSD. Even so, methodologies to assess ventricular volume are inconsistent and imprecise. ...
Unbalanced atrioventricular septal defect is an uncommon lesion with widely varying anatomic manifestations. When unbalance is severe, diagnosis and treatment is straightforward, directed toward single-ventricle palliation. Milder forms, however, pose a challenge to current diagnostic and therapeutic approaches. The transition from anatomies that are capable of sustaining biventricular physiology to those that cannot is obscure, resulting in uneven application of surgical strategy and excess mortality. Imprecise assessments of ventricular competence have dominated clinical decision making in this regard. Malalignment of the atrioventricular junction and its attendant derangement of inflow physiology is a critical factor in determining the feasibility of biventricular repair in the setting of unbalanced atrioventricular septal defect. The atrioventricular valve index accurately identifies unbalanced atrioventricular septal defect and also brings into focus a zone of transition from anatomies that can support a biventricular end state and those that cannot.
Hypoplastic left heart syndrome (HLHS) includes a group of closely related anomalies characterized by severe hypoplasia of the left-sided structures of the heart including rudimentary left ventricle, combinations of mitral and aortic valve stenosis, or atresia with diminutive ascending aorta and aortic arch. Here, the case of a 10-day-old male baby with a variant of HLHS is being reported.
The mechanisms responsible for heart failure in single-ventricle congenital heart disease are unknown. Using explanted heart tissue, we showed that failing single-ventricle hearts have dysregulated metabolic pathways, impaired mitochondrial function, decreased activity of carnitine palmitoyltransferase activity, and altered functioning of the tricarboxylic acid cycle. Interestingly, nonfailing single-ventricle hearts demonstrated an intermediate metabolic phenotype suggesting that they are vulnerable to development of heart failure in the future. Mitochondrial targeted therapies and treatments aimed at normalizing energy generation could represent a novel approach to the treatment or prevention of heart failure in this vulnerable group of patients.
Background
Infants with hypoplastic left heart syndrome (HLHS) or similar single ventricle cardiac lesions require a three-stage surgical approach, the first step being the Stage I Norwood procedure. The Queensland Children’s Hospital (QCH) in Australia is a tertiary hospital providing the only cardiac surgical service to children in Queensland and northern New South Wales.
Objective
To review the centre’s outcomes of Norwood procedures performed in the last 6 years.
Materials and Methods
We retrospectively evaluated all infants undergoing the stage I Norwood procedure between January 2015 and August 2021. Mortality, intensive care length of stay, events of cardiac arrest following surgery and duration of mechanical ventilation were calculated and analysed for subgroups depending on type of pulmonary shunt type (right-ventricle-to-pulmonary-artery shunt [RVPAS] vs the modified Blalock-Taussig shunt [MBTS]).
Results
Forty-nine (49) patients were included. Overall survival to stage two operation (Glenn) was 90%. Both shunts were used evenly with the RVPA conduit preferred for HLHS and the MBTS largely chosen for hypoplastic left heart variants. In univariable analysis there was no difference in cardiac arrest or mortality rate for the patient with a RVPAS compared to the patient with a MBTS.
Conclusion
We show that a recently established Norwood program can achieve results that are comparable to those reported by longer established centres, and the international literature.
Background
The routine use of angiotensin‐converting enzyme inhibitors (ACEI) during palliation of hypoplastic left heart syndrome is controversial. We sought to describe ACEI prescription in the interstage between stage 1 palliation (stage I Norwood procedure) discharge and stage 2 palliation (stage II superior cavopulmonary anastomosis procedure) admission using the NPC‐QIC (National Pediatric Cardiology Quality Improvement Collaborative) registry.
Methods and Results
Analysis of all patients (n=2180) enrolled in NPC‐QIC from 2008 to 2016 included preoperative anatomy, risk factors, and echocardiographic data. ACEI were prescribed at stage I Norwood procedure discharge in 38% of patients. ACEI prescription declined from 2011 to 2016 compared with pre‐2010 (36.8% versus 45%; P =0.005) with significant variation across centers (range 7–100%; P <0.001) and decreased prescribing rates associated with increased center volume ( P =0.004). There was no difference in interstage mortality ( P =0.662), change in atrioventricular valve regurgitation ( P =0.101), or change in ventricular dysfunction ( P =0.134) between groups. In multivariable analysis of all patients, atrioventricular septal defect (odds ratio [OR], 1.84; 95% CI, 1.28–2.65) or double outlet right ventricle (OR, 1.47; CI, 1.02–2.11), and preoperative mechanical ventilation (OR, 1.37; 95% CI, 1.12–1.68) were associated with increased ACEI prescription. In multivariable analysis of patients with complete echocardiographic data (n=812), ACEI prescription was more common with at least moderate atrioventricular valve regurgitation (OR, 1.88; 95% CI, 1.22–2.31).
Conclusions
ACEI prescription remains common in the interstage despite limited evidence of benefit. ACEI prescription is associated with preoperative mechanical ventilation, double outlet right ventricle, and atrioventricular valve regurgitation with marked inter‐center variation. ACEI prescription is not associated with reduction in mortality, ventricular dysfunction, or atrioventricular valve regurgitation during the interstage.
Despite advances in both medical and surgical therapies, individuals with single ventricle heart disease (SV) remain at high risk for the development of heart failure (HF). However, the molecular mechanisms underlying remodeling and eventual HF in SV patients are poorly characterized. Cardiolipin (CL), an inner mitochondrial membrane phospholipid, is critical for proper mitochondrial function, and abnormalities in CL content and composition are known in various cardiovascular disease etiologies. The purpose of this study was to investigate myocardial CL content and composition in failing and non-failing single right ventricle (RV) samples compared to normal control RV samples, assess mRNA expression of CL biosynthetic and remodeling enzymes, and quantitate relative mitochondrial copy number. A cross-sectional analysis of RV myocardial tissue from 22 failing SV (SVHF), 9 non-failing SV (SVNF), and 10 bi-ventricular control samples (BVNF) was performed. Expression of enzymes involved in CL biosynthesis and remodeling were analyzed using RT-qPCR and relative mitochondrial DNA copy number determined by qPCR. Normal phase high-pressure liquid chromatography coupled to electrospray ionization mass spectrometry was used to quantitate total and specific CL species. While mitochondrial copy number was not significantly different between groups, total CL content was significantly lower in SVHF myocardium compared to BVNF controls. Despite having lower total CL content however, the relative percentage of the major tetralinoleoyl CL species is preserved in SVHF samples relative to BVNF controls. Correspondingly, expression of enzymes involved in CL biosynthesis and remodeling were upregulated in SVHF samples when compared to both SVNF samples and BVNF controls.
Management of hypoplastic left heart syndrome (HLHS) is resource intensive. Heath care systems are pressured to provide value to patients by improving outcomes while decreasing costs. A single-center retrospective cohort of infants with HLHS who underwent Norwood procedure or hybrid Norwood from 2004 to 2014 and survived to first outpatient follow up were studied. The primary outcome was total cost through 12 months with a sub-analysis of patients with 60 months of data. Costs were calculated using internal cost accounting system and reported by cost center. Of the 152 HLHS patients identified, 69 met inclusion criteria. Stage I hospitalization (n = 69), with a median length of stay 34 days [interquartile range (IQR) 24–58 days], resulted in a median cost of $203,817 (IQR $136,236–272,453). Of survivors at 12 months (n = 55), the median cost was $369,393 (IQR $216,289–594,038) generated in part by a median of 67 (40–126 days) hospitalized days during that year. A subgroup analysis of patients who reached 60 months of age (n = 29) demonstrated a median total cost of $391,812 (IQR $293,801–577,443) and a median of 74 lifetime hospitalized days (IQR 58–116 days). High cost centers included intensive care (41%), non-ICU hospital (17%), operative services (11%), catheterization lab (9%), and pharmacy (9%). Using multiple regression analysis, significant drivers of cost included reoperation, length of hospitalization, low birthweight, and use of ECMO. Costs related to HLHS management are driven both by care-related complications such as surgical re-intervention and patient factors such as low birth weight.
This chapter describes the heterogeneous group of functionally single ventricle congenital heart defects. When caring for these infants, it is important to understand the unique anatomic variations of univentricular hearts and the physiology of the single ventricle circulation. The preoperative evaluation helps determine the most appropriate palliative surgical options, or the candidacy for recruitment of the hypoplastic ventricle for possible biventricular repair. Outcomes vary widely, and choosing the correct management strategy is critically important in this complex population.
Cardiac Resynchronization Therapy (CRT) has transformed the cardiac pacemaker into a powerful tool that improves function, decreases mortality, and increases quality of life in adult left ventricular heart failure patients. However, 30% of adult CRT patients are non-responders, prompting further evaluation of electro-mechanical coupling interactions in dyssynchrony and cardiac pacing to determine the optimal pacing sites and selection criteria for CRT. CRT in the pediatric heart failure population is even more difficult to evaluate due to complex anatomical abnormalities including single ventricles of left or right ventricular morphologies, and the higher proportion of right bundle branch block and right ventricular failure. The heterogeneous pediatric population has led to various pacing strategies for CRT with the ultimate goal of normalizing electrical and mechanical activation to preserve electromechanical synchrony and maximize cardiac function.
The first stage of surgical treatment for hypoplastic left heart syndrome (HLHS) includes the creation of artificial systemic-to-pulmonary connections to provide pulmonary blood flow. The modified Blalock-Taussig (mBT) shunt has been the technique of choice for this procedure; however, a right ventricle-pulmonary artery (RV-PA) shunt has been introduced into clinical practice with encouraging but still conflicting outcomes when compared with the mBT shunt. The aim of this study is to explore mathematical modeling as a tool for describing physical profiles that could assist the surgical team in predicting complications related to stenosis and malfunction of grafts in an attempt to find correlations with clinical outcomes from clinical studies that compared both surgical techniques and to assist the anesthesiologist in making decisions to manage patients with this complex cardiac anatomy. Mathematical modeling to display the physical characteristics of the chosen surgical shunt is a valuable tool to predict flow patterns, shear stress, and rate distribution as well as energetic performance at the graft level and relative to ventricular efficiency. Such predictions will enable the surgical team to refine the technique so that hemodynamic complications be anticipated and prevented, and are also important for perioperative management by the anesthesia team.
Background:
The two most common surgical strategies for the treatment of neonates born with single-ventricle anomalies associated with aortic arch obstruction are the Norwood operation and pulmonary artery banding plus coarctation repair (PAB+COA). We reviewed characteristics and outcomes of neonates who underwent those two surgical strategies at our institution.
Methods:
Between 2002 and 2012, 94 neonates with a single ventricle and aortic arch obstruction (excluding hypoplastic left heart syndrome) underwent Norwood (n = 65) or PAB+COA (n = 29). Outcomes were parametrically modeled, and risk factors associated with early and late death were analyzed.
Results:
Competing-risks analysis showed that, at 2 years after the operation, 24% of patients had died or received transplantation and 75% had undergone a Glenn shunt. At 5 years after the Glenn shunt, 10% of patients had died or received transplantation, 62% had undergone Fontan, and 28% were alive awaiting Fontan. Overall 8-year survival was 70%. Outcomes after Norwood included extracorporeal membrane oxygenation use in 9 (14%), unplanned reoperation in 13 (20%), hospital death in 10 (15%), and interstage death in 8 (12%), with 8-year survival of 66%. Outcomes after PAB+COA included extracorporeal membrane oxygenation use in 1 (3%), unplanned reoperation in 9 (30%), hospital death in 1 (3%), and interstage death in 3 (10%), with 8-year survival of 76%. There was an association trend between underlying anatomy and survival (hazard ratio [HR], 2.1; 95% confidence interval [CI], 0.9 to 4.7; p = 0.087). On multivariable analysis, factors associated with death were extracorporeal membrane oxygenation use (HR, 5.5; 95% CI, 1.9 to 15.9; p = 0.002), genetic syndromes/extracardiac anomalies (HR, 3.5; 95% CI, 1.5 to 8.2; p = 0.003), and weight of 2.5 kg or less (HR, 3.0; 95% CI, 1.3 to 7.2; p = 0.012).
Conclusions:
Anatomic and patient characteristics influence palliation outcomes in neonates born with single-ventricle anomalies associated with aortic arch obstruction. Although the Norwood operation is applicable in most of these patients, the PAB+COA strategy is a valid alternative in well-selected patients.
Patients with certain forms of congenital heart disease other than hypoplastic left heart syndrome require surgical management with single ventricle palliation. Anatomic considerations distinguish this group of patients from those with hypoplastic left heart syndrome. The initial evaluation, considerations for staged palliation, and postoperative management are discussed.
Objectives:
Empiric treatment with milrinone, a phosphodiesterase (PDE) 3 inhibitor, has become increasingly common in patients with single ventricle heart disease of right ventricular (RV) morphology (SRV); our objective was to characterize the myocardial response to PDE3 inhibition (PDE3i) in the pediatric population with SRV.
Study design:
Cyclic adenosine monophosphate levels, PDE activity, and phosphorylated phospholamban (PLN) were determined in explanted human ventricular myocardium from nonfailing pediatric donors (n = 10) and pediatric patients transplanted secondary to SRV. Subjects with SRV were further classified by PDE3i treatment (n = 13 with PDE3i and n = 12 without PDE3i).
Results:
In comparison with nonfailing RV myocardium (n = 8), cyclic adenosine monophosphate levels are lower in patients with SRV treated with PDE3i (n = 12, P = .021). Chronic PDE3i does not alter total PDE or PDE3 activity in SRV myocardium. Compared with nonfailing RV myocardium, SRV myocardium (both with and without PDE3i) demonstrates equivalent phosphorylated PLN at the protein kinase A phosphorylation site.
Conclusions:
As evidenced by preserved phosphorylated PLN, the molecular adaptation associated with SRV differs significantly from that demonstrated in pediatric heart failure because of dilated cardiomyopathy. These alterations support a pathophysiologically distinct mechanism of heart failure in pediatric patients with SRV, which has direct implications regarding the presumed response to PDE3i treatment in this population.
Hypoplastic left heart syndrome is characterized by severe underdevelopment of the structures in the left heart-aorta complex, including the left ventricular cavity and the aortic arch. This chapter elaborates:
1. Anatomy
2. Indication for surgery
3. Approach and cardiopulmonary bypass strategy
4. Norwood stage I palliation with double aortic cannulation and whole body perfusion (video)
5. Double barrel Damus-Kaye-Stansel anastomosis with reconstruction of the aortic arch and modified BT shunt (video)
6. Norwood stage I. palliation after bilateral pulmonary artery banding - staged approach (video)
7. Biventricular repair – the first stage: Norwood stage I. palliation with Sano shunt and enlargement of the ventricular septal defect (video)
8. Biventricular repair – the second stage: Intraventricular rerouting of the left ventricle to the systemic outflow and of the right ventricle to a pulmonary artery conduit (video)
The Norwood operation with various variants of the pulmonary-systemic shunts is presently successfully performed in newborns with hypoplastic left heart syndrome (HLHS). The most commonly employed modifications include the right Blalock-Taussig shunt (RBTS) and the right ventricle-to-pulmonary artery shunt (RV-PA). The report presents a modification of the Norwood procedure employed in a newborn with a double inlet left ventricle, transposition of the great arteries, hypoplastic right ventricle, left aortic arch and the right subclavian artery branching off the descending aorta. Due to the anatomical variant of the defect, the classic reconstruction of the aortic arch was performed with a homogeneous pulmonary artery patch, while the pulmonary-systemic shunt was achieved using a polytetrafluoroethylene graft interposed between the right pulmonary artery branch and the reconstructed ascending aorta strengthened by glutaraldehyde-fixed autogenous pericardium patches. The Norwood operation with some slight technical modifications may be used in an increasing spectrum of single ventricle type congenital heart defects as the preliminary stage of palliative treatment before the hemi-Fontan and Fontan operations.
Tricuspid atresia (TA) is a heterogeneous single-ventricle anomaly in which initial presentation and, consequently, timing and mode of palliation vary based on morphology and degree of pulmonary or systemic outflow obstruction. We report current era palliation outcomes and examine whether morphologic and, subsequently, surgical factors influence survival.
From 2002 to 2012, 105 infants with TA underwent surgical palliation. Competing risks analyses modeled events after first-stage surgery (Glenn versus death) and after Glenn (Fontan versus death) and examined risk factors affecting outcomes.
Seventy-eight patients (74%) required neonatal first-stage palliation, including modified Blalock-Taussig shunt (n = 46, 44%), Norwood (n = 18, 17%), and pulmonary artery band (n = 14, 13%), whereas 27 (26%) received primary Glenn as their initial surgery. Hospital mortality was 5 patients (4.8%). Competing risks models showed that by 1 year after first-stage surgery, 15% of patients had died and 83% had undergone Glenn. By 5 years after Glenn, 2% of patients had died and 80% had undergone Fontan. Overall 8-year survival was 84%. On multivariable analysis, risk factors for mortality were genetic/extracardiac anomalies (hazard ratio 7.0, 95% confidence interval: 2.4 to 20.6, p < 0.001) and pulmonary atresia (hazard ratio 4.4, 95% confidence interval: 1.6 to 12.2, p = 0.004). Survival was not affected by initial palliation type (p = 0.36), ventriculoarterial discordance (p = 0.25), systemic outflow obstruction (p = 0.84), or arch obstruction (p = 0.62).
Despite morphologic and physiologic variations necessitating different palliative sequences, multistage palliation outcomes of various TA subtypes are comparable and generally good, with the exception of patients with associated genetic/extracardiac anomalies. The bulk of mortality is interstage, indicating continued opportunity for improvement in monitoring and managing patients during this critical period.
Copyright © 2015 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.
We sought to review current-era experience with multistage palliation of neonates with hypoplastic left heart syndrome (HLHS) and to examine the patients' anatomic, and surgical risk factors influencing outcomes.
A retrospective review of 219 HLHS patients who underwent the Norwood operation from 2002 to 2012 was performed. Competing risks analyses modeled events after the Norwood operation (death/transplantation, progression to Glenn operation) and after the Glenn operation (death/transplantation progression to Fontan operation), and examined the risk factors affecting outcomes.
Competing risks analysis showed that 1 year after the Norwood operation, 25% of patients had died and 75% had undergone the Glenn operation. Three years after the Glenn operation, 11% of patients had died or received transplantation, 48% had undergone the Fontan procedure, and 41% were alive awaiting the Fontan. The overall 8-year survival after the Norwood operation was 66%. The risk factors for mortality on multivariable models were postoperative requirement for extracorporeal membrane oxygenation (hazard ratio [HR]: 3.1 [1.8-5.4], p < 0.001), genetic/major extracardiac anomalies (HR: 2.7 [1.4-5.2], p = 0.002), unplanned cardiac reoperation (HR: 2.5 [1.3-5.0], p = 0.007), modified Blalock-Taussig shunt use (HR: 2.4 [1.4-3.8], p < 0.001), and prematurity (HR: 1.9 [1.1-3.5], p = 0.030). Of note, anatomic factors such as HLHS subtype, ascending aorta diameter, restrictive atrial septum, and associated cardiac lesions did not affect outcomes (p > 0.10 each).
This current single-institution experience demonstrates that patients' factors (ie, prematurity, low weight, genetic/extracardiac anomalies) continue to adversely affect survival. Conversely, surgical and perioperative management advances, along with the use of the right ventricle to pulmonary artery shunt, might have neutralized the effects of anatomic factors on survival. Technical imperfections requiring reoperations are associated with failure to progress through palliation stages and diminished survival.
Copyright © 2015 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.
Subsequent to increased experience with the Norwood operation in children with hypoplastic left heart syndrome (HLHS), its application has expanded to allow palliation of single-ventricle (SV) malformations other than HLHS. We describe current palliation outcomes in this group of SV patients.
Between 2002 and 2012, 65 of the 303 Norwood operations were performed in non-HLHS SV patients. Competing risk analysis modeled events after Norwood and after subsequent Glenn and examined risk factors affecting outcomes.
Competing risk analysis showed that one year following Norwood, 24% of patients had died or received transplantation, 72% had undergone Glenn, and 4% were alive awaiting Glenn/Kawashima. Five years following Glenn, 9% of patients had died, 68% had undergone Fontan, and 23% were alive awaiting Fontan. Overall seven-year survival following Norwood was 68%. On multivariable analysis, mortality risk factors were unplanned cardiac reoperation (hazard ratio [HR]: 4.0 [1.5-10.6], P = .006), right dominant ventricle morphology (HR: 3.3 [1.3-8.3], P = .012), and postoperative extracorporeal membrane oxygenation (HR: 3.1 [1.1-9.0], P = .035).
Operative death and interstage mortality continue to be problematic following Norwood palliation for non-HLHS SV variants. Outcomes seem comparable to those reported for HLHS, however they are influenced by underlying pathology; children with dominant left ventricle morphology (tricuspid atresia and double inlet left ventricle) have superior survival compared to those with dominant right ventricle morphology (mitral atresia, unbalanced atrioventricular septal defect, and most patients with atrial isomerism). Unplanned reoperations for technical imperfections diminish survival. Large multicenter studies might be warranted to better identify high-risk patients and provide guidance toward improving their survival.
© The Author(s) 2014.
INTRODUCCION La antigua concepción de Galeno acerca de la circulación sanguínea fue solo rectificada por el trabajo de Colombo y Harvey, quienes en pleno renacimiento y edad moderna, describieron el conocimiento actual de lo que entendemos por circulación pulmonar y sistémica (1). La característica fisiológica fundamental del corazón univentricular es que el ventrículo único se encuentra siempre sobrecargado, ya que siempre está a cargo de la circulación pulmonar y sistémica. La necesidad de tener una circulación pulmonar dependiente de un ventrículo no fue cuestionada hasta el siglo 20 cuando Rodbard (1) en 1948 realiza un by pass de ventrículo derecho en perros anastomosando la orejuela derecha a la arteria pulmonar ligada proximalmente. Este logro épico de la cirugía experimental dio el puntapié inicial a la introducción clínica de diversos procedimientos como la operación de Glenn (2), de Fontan (3) y de Kreutzer (4). A lo largo de las tres ultimas décadas se ha establecido que el objetivo final en el tratamiento de las cardiopatías univentriculares es la creación de un sistema hemodinámico en el cual el retorno venoso sistémico es derivado hacia las arterias pulmonares sin pasar por el ventrículo. De esta manera el ventrículo único funciona como una bomba aspirante y expelente y en su faz aspirante se encarga pasivamente la circulación pulmonar y en su faz expelente se dedica exclusivamente a la circulación sistémica. Sin lugar a dudas, para que este sistema hemodinámico funcione dos requisitos básicos se tiene que cumplir a rajatabla: Resistencias pulmonares bajas y presión de fin de diástole baja del Ventrículo sistémico. Cualquier causa que provoque un aumento de estas dos variables como un neumotórax o una arritmia traerá aparejada la disfunción del sistema con el aumento de la presión venosa central y la aparición de edemas periféricos. El largo camino del Fontan Kreutzer ha sido caracterizado por el desarrollo de diversas técnica para llevar el retorno venoso sistémico hacia las arterias pulmonares. El objetivo de este capítulo es repasar los últimos 30 años de historia de este procedimiento poniendo especial énfasis en los distintos abordajes quirúrgicos y en los desafíos actuales.
Prior studies evaluating the association of HLHS anatomic variants and mortality report conflicting results. Our objective was to determine if antegrade flow across the mitral within variants of HLHS with aortic atresia is associated with increased mortality compared to ventricular hypoplasia variants without antegrade mitral flow. All patients with HLHS born between 2002 and 2011 year who underwent stage I Norwood palliation with complete history and echocardiograms for patency of the mitral and aortic valves were studied. The cohort was divided into three groups: aortic atresia-mitral atresia (AA-MA), aortic stenosis-mitral stenosis (AS-MS), and aortic atresia-mitral stenosis (AA-MS). Demographic, comorbidities, and operative variables were analyzed. Analysis of variance techniques was applied for continuous variables and categorical variables. Survival analysis was performed using the Kaplan-Meier method with log-rank testing. A total of 70 consecutive patients who underwent Norwood Procedure were analyzed. There were no statistical differences in gender, birth weight, and age at time of Norwood procedure. Thirty patients had AA-MA variant, 23 had AA-MS, and 17 had AS-MS. Long-term Norwood survival was 60 % for AA-MA, 65 % for AS-MS, and 26 % for AA-MS (p = 0.043). Use of extracorporeal membrane oxygenation as well as shunt revisions was more frequent for the AA-MS compared to other variants (p < 0.05). Patient weight at time of Norwood and length of regional perfusion were the highest predictors for hospital death following Norwood procedure. The Norwood procedure for mitral stenosis and aortic atresia is more often associated with use of extracorporeal membrane oxygenation and shunt revision compared to other variants. This HLHS variant has lowest long-term survival.
Left ventricular hypoplasia complicates other forms of congenital heart disease in addition to the classic “hypoplastic left heart syndrome.” Within this heterogeneous group, subtle anatomic differences determine surgical management and ultimate prognosis. Thus, an individualized approach is necessary to optimize outcomes in this complex population.
The objective of this study is to identify predictors of prolonged intensive care unit (ICU) length of stay (LOS) for single ventricle patients following Stage I palliation. We hypothesize that peri-operative factors contribute to prolonged ICU stay among children with hypoplastic left heart syndrome (HLHS) and its variants. In 2008, as a part of the Joint Council on Congenital Heart Disease initiative, the National Pediatric Cardiology-Quality Improvement Collaborative established a data registry for patients with HLHS and its variants undergoing staged palliation. Between July 2008 and August 2011, 33 sites across the United States submitted discharge data essential to this analysis. Data describing the patients, their procedures, and their hospital experience were entered. LOS estimates were generated. Prolonged LOS in the ICU was defined as stay greater than or equal to 26 days (i.e., 75th percentile). Statistical analyses were carried out to identify pre-operative, operative, and post-operative predictors of prolonged LOS in the ICU. The number of patients with complete discharge data was 303, and these subjects were included in the analysis. Univariate and multivariate analyses were performed. Multivariate analysis revealed that lower number of enrolled participants (e.g., 1-10) per site, the presence of pre-operative acidosis, increased circulatory arrest time, the occurrence of a central line infection, and the development of respiratory insufficiency requiring re-intubation were associated with prolonged LOS in the ICU. Prolonged LOS in the ICU following Stage I palliation in patients with HLHS and HLHS variant anatomy is associated with site enrollment, circulatory arrest time, pre-operative acidosis, and some post-operative complications, including central line infection and re-intubation. Further study of these associations may reveal strategies for reducing LOS in the ICU following the Norwood and Norwood-variant surgeries.
Patients requiring extracorporeal membrane oxygenation (ECMO) support after a Norwood operation constitute an extremely high-risk group. Data regarding risk factors for the requirement for ECMO post-Norwood are limited, however. We retrospectively assessed risk factors for requiring ECMO support after a Norwood operation during a 10-year period in a high-volume center.
Retrospective case-control study of 64 consecutive patients requiring ECMO support after a Norwood operation at a single institution during a 10-year period (January 2001-December 2010), with a 3:1 era-matched control group of patients who underwent a Norwood but did not require ECMO.
In univariate analysis, ascending aorta less than 2.0 mm, longer cardiopulmonary bypass (CPB) time, intraoperative shunt revision, and right ventricle to pulmonary artery conduit were associated with the need for postoperative ECMO. A single left ventricle was protective compared with single right ventricle anatomy. By multivariate logistic regression, birth weight less than 2.5 kg and longer CPB time were independently associated with the need for postoperative ECMO. Receiver-operating characteristic curve analysis identified a peak lactate of 9 mmol/L and a peak vasoactive inotrope score (VIS) of 27 within 48 hours of surgery as most prognostic of the need for ECMO.
Birth weight less than 2.5 kg and longer CPB time are independently associated with the need for ECMO after a Norwood operation. Peak serum lactate and peak VIS may be useful in stratifying risk for ECMO. Risk factors for ECMO post-Norwood appear to be similar to the risk factors for early mortality post-Norwood.
Zusammenfassung Im Gegensatz zu anderen angeborenen Herzfehlern ist für das hypoplastische Linksherzsyndrom (HLHS) erst innerhalb der letzten Jahre eine zunehmend standardisierte und erfolgversprechende Behandlung entwickelt worden. So bereitete es lange große Schwierigkeiten, den postnatal drohenden Kreislaufschock zu behandeln oder gar ihn zu vermeiden und die Neugeborenen in gutem Zustand zur Operation zu bringen. Es ist eine kardial nicht mehr kompensierbare pulmonale Hyperperfusion zu vermeiden und ein hinreichendes systemisches Herzzeitvolumen zu gewährleisten, was am besten und einfachsten durch Verzicht auf künstliche Beatmung und eine starke pharmakologische systemische Nachlastsenkung gelingt. Chirurgisch hat speziell die Einführung der selektiven hypothermen zerebralen Perfusion eine drastische Verkürzung der Kreislaufstillstandzeiten ermöglicht. Postoperativ ist ein ausgeklügeltes Kreislaufmonitoring zur Gewährleistung eines ausreichenden systemischen Sauerstoffangebots erforderlich, was therapeutisch wiederum durch eine starke Nachlastsenkung (speziell-Blocker) erreicht wird. Die Hospitalletalität der Norwood-Operation konnte in erfahrenen Kinderherzzentren auf 10–15% gesenkt werden. Die Komplettierung der Kreislauftrennung erfolgt zweistufig durch eine obere kavopulmonale Verbindung im Alter von 4 bis 6 Monaten und die Komplettierung der Fontan-Zirkulation ab dem 3. Lebensjahr.
Patients with double inlet left ventricle (DILV)/transposition and similar morphologies have their systemic outflow traverse a bulboventricular foramen (BVF), which has a propensity to narrow over time. The aim of this study is to evaluate the outcomes of initial pulmonary artery banding (PAB) compared with the Norwood-type reconstruction in neonates.
A retrospective study of children with DILV and similar morphologies presenting between 1982 and 2012. The outcomes of initial PAB (n = 17) are compared with a Norwood-type reconstruction (n = 20). The two groups were similar with respect to age, gender, weight, noncardiac syndromes, and Fontan completion. Mean follow-up was longer in PAB patients (13.3 ± 9.8 years) versus Norwood (4.5 ± 3.0 years, p = 0.001).
Survival was 75% at eight years in the Norwood group versus 71% in the PAB group (p = 0.76). Mortality in the Norwood group was higher before 2002 (p = 0.06). The age of patients who underwent a bidirectional Glenn shunt was significantly higher for PAB group (PAB, 9.1 ± 1.4 months vs. Norwood, 6.1 ± 1.6 months; p < 0.001). Freedom from any type of reintervention (systemic outflow obstruction or coarctation) was similar (Norwood, 83% vs. PAB, 71%; p = 0.62). Freedom from heart block with a pacemaker insertion was significantly better for Norwood patients (Norwood, 89% vs. PAB, 41%; p = 0.001).
The Norwood-type reconstruction provides good palliation in this subgroup of patients and avoids the need for subsequent intracardiac operations, maintaining an unobstructed systemic outflow tract and avoiding the risk of heart block. Survival does not differ depending on the type of procedure. Patients with PAB show comparable satisfactory early and long-term results, with an increasing reoperation risk and heart block remaining a major concern.
Hypoplastic left heart syndrome was once considered a lethal congenital heart defect; yet, the prognosis is improving with advances in health care. Many ethical dilemmas still surround this diagnosis and treatment. This article explores the ethical side of hypoplastic left heart syndrome care. Copyright 2002, Elsevier Science (USA). All rights reserved.
BACKGROUND Failure of infants with critical aortic stenosis to survive after adequate valvotomy despite a left ventricular size that appears to be adequate indicates that additional preoperative anatomic features may contribute to mortality.
METHODS AND RESULTS Discriminant analysis was used to determine which of several echocardiographically measured left heart structures were independent predictors of survival after valvotomy for neonatal critical aortic stenosis. It was possible to predict outcome after classic valvotomy (two-ventricle-type repair) with 95% accuracy based on mitral valve area, long-axis dimension of the left ventricle relative to the long-axis dimension of the heart, diameter of the aortic root, and body surface area. Left ventricular volume was not a major determinant in this study, in part because patients who had initial valvotomy had been preselected in favor of an adequately sized left ventricle. Patients with multiple small left ventricular structures were found to have significantly improved survival after initial Norwood operation. In contrast, balloon valvotomy with subsequent Norwood procedure was usually unsuccessful.
CONCLUSIONS The adverse effects of small inflow, outflow, and/or cavity size of the left ventricle are cumulative. The accuracy of prediction of outcome based only on preoperative anatomy indicates that adequacy of valvotomy is not generally a limiting factor for survival in this group of patients. It is possible to identify subjects whose chance of survival is better after a Norwood procedure rather than valvotomy, even if left ventricular volume is not critically small.
This article examines the accuracy of normal approximations to confidence limits for the binomial (n,p) parameter p. The method of getting “exact” values from an F table is too slow for practical use and useless for large n. The two usual approximations have unsatisfactory accuracy both for small n and asymptotically, and the simpler one lacks an invariance property of the confidence limit. P. Hall’s [Biometrika 69, 647-652 (1982; Zbl 0493.62036)] approximation also lacks invariance and, even when symmetrized, has unsatisfactory accuracy. J. W. Pratt’s [J. Am. Sta. Assoc. 63, 1457-1483 (1968; Zbl 0167.474)] approximation has excellent accuracy for all n. Inversion of a W. Molenaar [Approximations to the Poisson, binomial and hypergeometric distribution functions. Mathematical Centrum, Amsterdam (1973)] normal approximation to the binomial gives better asymptotic accuracy than Pratt’s approximation, but poor values for observations close to n.
Objective: Controversy persists with regard to the treatment of patients with aortic atresia. Staged reconstructive operations and primary transplantation have been advocated as treatment strategies, but in many instances no treatment is undertaken. A multi-institutional study was undertaken for the purpose of characterizing this challenging patient group, comparing the prevalence and outcomes of the various treatment strategies, and identifying potential predictors of success or failure with each. Methods and results: A total of 323 neonates with aortic atresia were entered into a 21-institution prospective, nonrandomized study between January 1, 1994, and January 1, 1997. Three protocols were used, nonexclusively in many institutions: (1) staged reconstructive surgery with initial palliation by a Norwood procedure and eventual Fontan operation, (2) heart transplantation as initial definitive therapy, and (3) nonsurgical management. Analysis was based on initial protocol assignment: staged reconstructive surgery in 253 patients, heart transplantation in 49 patients, and nonsurgical management in 21 patients. For all patients initially entered into the 2 surgical treatment protocols, survival at 1, 3, 12, 24, and 36 months after entry was 67%, 59%, 52%, 51%, and 50%, respectively. A multivariable analysis found incremental risk factors for death at any time after entry to be lower birth weight (P = .04), associated noncardiac anomaly (P = .007), and entry into the nonsurgical protocol (P < .0001) or the staged reconstructive surgery protocol (P = .03). Four institutions had higher survival statistics; 2 used a heart transplantation protocol and 2 used a staged reconstructive surgery protocol. For the 113 patients treated at these 4 institutions, survival at 1, 3, 12, 24, and 36 months after entry was 77%, 70%, 64%, 62%, and 61%, respectively. Survival among the 4 institutions was similar (P = 0.1). Conclusions: Among patients with aortic atresia, other features of cardiac structure including aortic size, degree of left ventricular hypoplasia, and degree of mitral hypoplasia or atresia are not predictive of survival from 2 surgical protocols. The highest survival was achieved with either treatment strategy at institutions strongly committed to the use of one or the other surgical management protocol. (J Thorac Cardiovasc Surg 1998;116:417-31)
Background:
The treatment of infants with hypoplastic left heart syndrome has been challenging and controversial.
Methods:
To assess the operative management and intermediate-term outcome, we retrospectively analyzed our surgical experience with 50 newborns with hypoplastic left heart syndrome operated on between January 1989 and June 1995.
Results:
Surgical palliation with a first-stage Norwood operation was offered to 28 patients. The remaining 22 infants were initially listed for heart transplantation, and 15 underwent the operation. Ten of the 15 recipients are alive, and all are in New York Heart Association class I. Seven infants underwent a Norwood procedure after being on the list for transplantation for 12 to 42 days. A total of 34 patients underwent Norwood procedures with one operation aborted because of inoperable anatomy. Two infants who survived the first-stage Norwood operation underwent subsequent heart transplantation and are currently doing well. The 1-year mortality rate for heart transplantation was 18% (3/17) versus 50% (17/34) for the Norwood procedure. Risk factors for early mortality after a Norwood procedure include longer circulatory arrest time (> 50 minutes), preoperative acidosis (pH < 7.20), larger systemic-pulmonary artery shunt (> or = 4 mm), diminutive ascending aorta (< or = 2.0 mm), and anatomic subtype of aortic and mitral atresia. The 1-year survival rate for the Norwood procedure improved from 36% for the patients operated on during 1989 through 1992 to 75% during 1993 to mid-1995 (p = 0.005). Of the 17 survivors of a first-stage Norwood operation, 10 have undergone the second stage (bidirectional Glenn procedure), and 7 have completed a Fontan procedure. Heart transplantation results have also improved, with no deaths since 1992.
Conclusions:
Both the Norwood procedure and heart transplantation have encouraging early to intermediate results in infants with hypoplastic left heart syndrome. Hypoplastic left heart syndrome should be managed selectively on the basis of cardiac morphology, donor availability, and family wishes. Development of a flexible program involving the use of both procedures may aid in the successful management of infants with hypoplastic left heart syndrome.
Failure of infants with critical aortic stenosis to survive after adequate valvotomy despite a left ventricular size that appears to be adequate indicates that additional preoperative anatomic features may contribute to mortality.
Discriminant analysis was used to determine which of several echocardiographically measured left heart structures were independent predictors of survival after valvotomy for neonatal critical aortic stenosis. It was possible to predict outcome after classic valvotomy (two-ventricle-type repair) with 95% accuracy based on mitral valve area, long-axis dimension of the left ventricle relative to the long-axis dimension of the heart, diameter of the aortic root, and body surface area. Left ventricular volume was not a major determinant in this study, in part because patients who had initial valvotomy had been preselected in favor of an adequately sized left ventricle. Patients with multiple small left ventricular structures were found to have significantly improved survival after initial Norwood operation. In contrast, balloon valvotomy with subsequent Norwood procedure was usually unsuccessful.
The adverse effects of small inflow, outflow, and/or cavity size of the left ventricle are cumulative. The accuracy of prediction of outcome based only on preoperative anatomy indicates that adequacy of valvotomy is not generally a limiting factor for survival in this group of patients. It is possible to identify subjects whose chance of survival is better after a Norwood procedure rather than valvotomy, even if left ventricular volume is not critically small.
Aortic atresia is a form of hypoplastic left heart syndrome always complicated by associated severe hypoplasia of the ascending aorta and various degrees of mitral valve and left ventricular hypoplasia. At present it is a universally fatal lesion in early infancy. This is a report of a new palliative procedure for hypoplastic left heart syndrome that has resul;ed in early ongoing survival of two infants with aortic atresia. On the basis of experience with a third patient, an operation for future physiologic correction is proposed.
Norwood's operation provides satisfactory palliation for neonates with hypoplastic left heart syndrome. The dominant physiologic features of hypoplastic left heart syndrome, ductal dependency of the systemic circulation and parallel pulmonary and systemic circulations, are shared by a multitude of other less common congenital heart malformations. Theoretically, these should be equally amenable to palliation by Norwood's operation. Between January 1990 and June 1994, 60 neonates with malformations other than hypoplastic left heart syndrome underwent initial surgical palliation by Norwood's procedure. Diagnoses included single left ventricle with levo-transposition of the great arteries (12); critical aortic stenosis (8); complex double-outlet right ventricle (8); interrupted aortic arch with ventricular septal defect and subaortic stenosis (7); ventricular septal defect, subaortic stenosis, and coarctation of the aorta (7); aortic atresia with large ventricular septal defect (6); tricuspid atresia with transposition of the great arteries (6); heterotaxy syndrome with subaortic obstruction (3); and other (3). There were 10 hospital deaths and 50 survivors (83% survival). After the introduction of inspired carbon dioxide therapy into the postoperative management protocol (1991), 42 of 47 patients survived (89% survival). Mortality was independent of diagnosis and essentially the same as that for hypoplastic left heart syndrome. With minor technical modifications, Norwood's operation provides satisfactory initial palliation for a wide variety of malformations characterized by ductal dependency of the systemic circulation in anticipation of either a Fontan procedure or a biventricular repair.
We conducted a retrospective study of 78 patients who underwent palliative reconstructive operation for hypoplastic left heart syndrome representing an entire consecutive experience between 1983 and 1991 to identify predictors of mortality that might enable more appropriate triage of patients to either reconstruction or transplantation. Twenty-nine patients had aortic atresia, mitral atresia; 18 had aortic stenosis, mitral stenosis; 20 had aortic atresia and mitral stenosis; and 11 had miscellaneous forms of hypoplastic left heart syndrome. There were 29 hospital deaths (37%). A worst preoperative pH (p = 0.01) and immediate preoperative pH (p = 0.03) less than the median were predictors of hospital mortality. The anatomic subgroup aortic atresia, mitral stenosis (p = 0.06) had a possible increased hospital mortality. One patient was lost to follow-up. The Kaplan-Meier survival estimate among hospital survivors was 34% at 3 years and 25% at 5 years. The anatomic subgroup aortic atresia, mitral atresia (p = 0.02) had a worse late outcome (11% 3-year survival) whereas the subgroup aortic stenosis, mitral stenosis (p = 0.04; 76% 3-year survival) had a better late outcome. There were no other significant predictors of late survival other than immediate prerepair pH (p = 0.05). Interpretation of this experience is complicated by the large number of different surgical techniques used for both first-stage neonatal reconstruction and the Fontan procedure plus introduction of the bidirectional Glenn shunt as an intermediate step midway through the experience. Nevertheless in this time frame and with the variety of techniques used, this experience demonstrates that patients with aortic atresia, mitral atresia, particularly those who have been very acidotic in the neonatal period, are least likely to do well with the reconstructive approach to hypoplastic left heart syndrome and are the most appropriate subgroup to be directed to transplantation. Patients with aortic stenosis, mitral stenosis have an excellent late outcome with the reconstructive approach.
Although the first-stage Norwood procedure mostly has been used for hypoplastic left heart syndrome, there are other anomalies in which the Norwood procedure can be applied. Since 1991, 18 newborns without hypoplastic left heart syndrome underwent a first-stage Norwood procedure. All had a hypoplastic aortic annulus, ascending aorta, and transverse aorta. Ten had normally related great arteries: aortic atresia or aortic stenosis with inadequate left ventricle in 4, mitral atresia or stenosis in 4, and interrupted aortic arch in 2. The 8 others had double-outlet right ventricle with mitral atresia or complete transposition with a hypoplastic right ventricle. Age ranged from 2 to 77 days (median, 6 days) and weight from 2.4 to 4.4 kg (mean, 3.0 kg). The patients with interrupted aortic arch simultaneously underwent primary repair of the interruption. There were 17 hospital survivors (94%). There have been no late deaths in follow-up from 4 to 30 months (mean, 15.5 months). Thirteen children have had subsequent creation of a bidirectional Glenn shunt with takedown of the original systemic to pulmonary shunt. The 2 with interrupted aortic arch underwent a Rastelli-type biventricular repair. These results show that the Norwood procedure can be applied to infants without hypoplastic left heart syndrome who have hypoplastic aortas and excessive pulmonary blood flow with very low mortality and excellent palliation.
Ventricular-ventricular interaction is known to occur in normal human heart. To determine whether it plays a role in the function of single right ventricles, systemic right ventricles were compared with and without a left ventricle mechanically coupled to it.
A noninvasive magnetic resonance tagging technique (spatial modulation of magnetization [SPAMM]) that lays intersecting stripes down on the myocardium was used to examine 18 patients with systemic right ventricles: 7 with a single right ventricle who have undergone the Fontan procedure (age, 38.8 +/- 8.9 months) and 11 with transposition of the great arteries who have undergone an atrial inversion operation (age, 16.3 +/- 3.9 years). The motion of the intersection points was tracked through systole to determine regional twist and radial shortening. Shortening rates also were evaluated. Finite strain analysis was applied to the grid lines using Delaunay triangulation, and the two-dimensional strain tensor and principal E1 strains were derived for the various anatomic regions. Basal and apical short-axis planes through the ventricular wall were categorized into four distinct regions spaced equally around the circumference of the slice. We observed the following results. (1) Strain was greatest and heterogeneity of strain was least in patients with transposition of the great arteries who were status post atrial inversion operation (six of eight regions). Marked differences were noted in the distribution of strain within a given region, from endocardium to epicardium, and from atrioventricular valve to apical plane between patient subtypes and those with a normal left ventricle. (2) Contrary to the normal subject studied by the use of the same method, for both patient subtypes, there was counterclockwise twist in one region, clockwise twist in the posterior or inferior wall, and a transition zone of no twist at which the two regions of twist met. Normal human adult left ventricles studied in short-axis twist uniformly counterclockwise as viewed from apex to base. (3) Radial inward motion was greatest in the superior wall of both types of systemic right ventricle. The inferior walls of Fontan patients and the posterior (ie, septal) walls of patients with transposition of the great arteries, status post atrial inversion, moved paradoxically in systole. The shortening rate at the atrioventricular valve of patients with transposition of the great arteries, status post atrial inversion, was significantly lower than at the apex or in Fontan patients.
Marked differences in regional wall motion and strain were demonstrated in systemic right ventricles, depending on whether a left ventricle was present to augment its function. Ventricular-ventricular interaction appears to play an important role in affecting the biomechanics of systemic right ventricles. These observations were markedly different from those in the normal systemic left ventricle. These techniques demonstrate tools with which we can begin to evaluate surgical outcomes using regional myocardial mechanics and may provide a clue to single right ventricle failure.
A pediatric cardiac surgeon performed 104 neonatal arterial switch operations for transposition of the great arteries with or without ventricular septal defect between June 1987 and February 1993. Initial euphoria on having only one death in the first 52 patients gave way to increasing concern when patients 53, 55, 59, 63, 64, 67, and 68 died. Sensing a problem, the surgeon visited a low-risk institution after patients 55 and 64 had died and then decided to re-train after patient 68 died. One death has occurred since. To find out whether the cluster of failures could have been related to chance alone, to variability of risk factors across time, or to suboptimal performance, we conducted the following analyses: First, identification of trends with the cumulative sum procedure was undertaken and actual mortality compared with the mortality predicted from an equation derived from a multi-institutional study. Second, logistic regression analysis of risk factors was done. If a mechanism of continuous monitoring had been in place, unfavorable trends and a need for change in protocol would have been detected earlier. Retrospective risk factor analysis suggested an excessive risk for patients with origin of the circumflex or left anterior descending coronary arteries from sinus 2 and a protective effect of phenoxybenzamine. However, about half of the risk associated with the cluster of failures was not accounted for by the variables analyzed. There was therefore an indication of suboptimal performance that appears to have been neutralized by retraining.
Infant cardiac transplantation for hypoplastic left heart syndrome (HLHS) can be performed with a high success rate, but it remains unclear whether variations in anatomy or degree of illness before transplantation can affect ultimate survival.
We analyzed the initial echocardiograms and pretransplant courses of 21 infants whose families chose transplantation as a primary therapy option for factors influencing survival. Sixteen of 21 were transplanted (mean wait, 18 days; range, 3 to 97 days) with 15 current (6- to 36-month) survivors, leading to a survival rate from presentation of 71% (70% confidence limit [CL], 61% to 81%) and an operative survival of 94% (70% CL, 81% to 99%). Seven of 20 listed for transplant (35%) had a severely restrictive interatrial communication, defined as a color flow jet width of 3 mm or less across the interatrial septum. Three of these 7 infants died at 4 (2) and 7 (1) weeks from congestive heart failure and progressive hypoxemia before transplantation. One died 2 months after transplant with an autopsy demonstrating pulmonary venous hypertensive disease, leading to a significantly higher relative risk for death (relative risk = 7.4, P = .01) for those infants with a severely restrictive interatrial communication versus those infants without severe restriction. The size and function of the right ventricle, left atrium, aorta, and tricuspid valve, as well as the magnitude of support on presentation, were not related to ultimate survival.
A severely restrictive interatrial communication is a frequent component of HLHS. When primary cardiac transplantation is the chosen therapy for HLHS, it is a significant negative risk factor for death primarily before transplantation.
The authors review their experience with staged reconstructive surgery for hypoplastic left heart syndrome (HLHS) and assess current outcome for this condition.
Once considered a uniformly fatal condition, the outlook for newborns with HLHS has been altered dramatically with staged reconstructive procedures. Refinements in operative technique and perioperative management have been largely responsible for this improved outlook.
The authors reviewed their experience with 158 consecutive patients undergoing stage 1 reconstruction with a Norwood procedure from January 1990 to August 1995. All patients had classic HLHS, defined as a right ventricular dependent circulation in association with atresia or severe hypoplasia of the aortic valve.
There were 120 hospital survivors. Among the 127 patients considered at standard risk, survival was significantly higher than that for the 31 patients with important risk factors. Adverse survival was associated most strongly with significant associated noncardiac congenital conditions and severe preoperative obstruction to pulmonary venous return. Second-stage reconstruction with the hemi-Fontan procedure was performed in 106 patients, with 103 hospital survivors and one late death. Three of the late survivors were not considered candidates for the Fontan procedure. To date, the Fontan procedure has been completed in 62 patients, with 53 survivors. Deaths after the Fontan procedure occurred early in our experience and were mostly secondary to left pulmonary artery stenosis or hypoplasia. Significant or potentially significant morbid conditions were noted in 25 of the 120 hospital survivors. Neurologic conditions were found in 6% and cardiovascular conditions in 10%, including dysrhythmia, left pulmonary artery thrombosis, and chronic pleural effusions. Among the patients considered at standard risk with typical anatomy, actuarial survival was 69 +/- 8% at 5 years. Survival was 71 +/- 17% at 5 years for standard risk patients with variant anatomy and 58 +/- 9% for the entire cohort of 158 patients. The largest decrease in survival occurred in the first month of life and late deaths primarily affected those patients in the high-risk group.
Staged reconstruction has significantly improved the intermediate-term outlook for patients with HLHS. Factors addressing improvements in early (< 1 month) first-stage survival would be expected to add significantly to an overall improved late outcome. Currently employed refinements in operative technique are associated with eliminating or reducing pulmonary artery distortion and dysrhythmia.
The optimal approach to hypoplastic left heart syndrome (HLHS) is controversial. The palliative Norwood operation, cardiac transplantation, and no surgical intervention have all been advocated. Centers that perform the Norwood operation have met with varied results, and conflicting reports exist regarding factors predictive of stage I outcome. From January 1990 to January 1996, 67 patients with HLHS were admitted with intent to perform the staged Norwood procedure. Fourteen patients did not undergo surgery. In the 53 patients treated surgically, outcome was reviewed, and 10 potential risk factors for first stage mortality were analyzed. Forty-one infants survived the Norwood I operation to hospital discharge (77% of the surgically treated patients and 61% of the entire group, including those who did not undergo operation) with 6 additional deaths 3 to 5 months after operation. Univariate analysis showed cardiopulmonary bypass time and circulatory arrest time to be significant risk factors for hospital mortality. Multivariate analysis revealed only cardiopulmonary bypass time as significant (p <0.01). Of the 15 prenatally diagnosed newborns who underwent surgery, 11 survived (p = 0.72). Ten of 11 patients with preoperative organ damage survived (p = 0.42). Among the 35 bidirectional Glenn (Norwood II) and Fontan (Norwood III) procedures performed, there were 2 deaths. The 5-year actuarial survival for patients who underwent operations was 61%. The Norwood procedure is a favorable option for the infant with HLHS. Surgical survival may be affected by a prolonged cardiopulmonary bypass time, but is not affected by other factors analyzed, including prenatal diagnosis and preoperative organ damage.
The purpose of this study was to review a large, evolving, single-center experience with the Fontan operation and to determine risk factors influencing early and late outcome.
The first 500 patients undergoing modifications of the Fontan operation at our institution were identified. Perioperative variables were recorded and a cross-sectional review of survivors was undertaken.
The incidence of early failure decreased from 27.1% in the first quartile of the experience to 7.5% in the last quartile. In a multivariate model, the following variables were associated with an increased probability of early failure: a mean preoperative pulmonary artery pressure of 19 mm Hg or more (p < 0.001), younger age at operation (p = 0.001), heterotaxy syndrome (p = 0.03), a right-sided tricuspid valve as the only systemic atrioventricular valve (p = 0.001), pulmonary artery distortion (p = 0.04), an atriopulmonary connection originating at the right atrial body or appendage (p = 0.001), the absence of a baffle fenestration (p = 0.002), and longer cardiopulmonary bypass time (p = 0.001). An increased probability of late failure was associated with the presence of a pacemaker before the Fontan operation (p < 0.001). A morphologically left ventricle with normally related great arteries or a single right ventricle (excluding heterotaxy syndrome and hypoplastic left heart syndrome) were associated with a decreased probability of late failure (p = 0.003).
These analyses indicate that early failure has declined over the study period and that this decline is related in part to procedural modifications. A continuing late hazard phase is associated with few patient-related variables and does not appear related to procedural variables.
Patients with univentricular hearts and ventriculoarterial discordance with potentially obstructed systemic blood flow continue to pose difficult management problems. The goals of neonatal palliative operations are to control pulmonary blood flow while avoiding pulmonary artery distortion, to relieve systemic outflow tract obstruction, and to avoid heart block.
Between January 1987 and December 1996, 38 patients with either tricuspid atresia or a double-inlet left ventricle and ventriculoarterial discordance underwent a modified Norwood procedure. Their mean age was 15 days, and their mean weight was 3.4 kg. Aortic arch anomalies were present in 92% of the patients. Morbidity and mortality statistics, intraoperative data, and postoperative echocardiograms were reviewed.
There were 3 early deaths (7.8%) and 5 late deaths (13.1%). The actuarial survival rates at 1 month, 1 year, and 5 years were 89%, 82%, and 71%, respectively. Follow-up was complete in all children at a mean interval of 30 +/- 9 months. None of the patients had significant neoaortic valve insufficiency, and 1 patient required therapy for residual aortic arch obstruction. Nine patients (30% of the survivors) have undergone the hemi-Fontan procedure, and 18 patients (60%) successfully have undergone the Fontan procedure.
In this patient population, we recommend the modified Norwood procedure as the neonatal palliative treatment of choice. It can be performed with acceptable early morbidity and mortality, and it improves suitability for the Fontan procedure. It reliably relieves all levels of systemic outflow tract obstruction, controls pulmonary blood flow, and avoids heart block.
Competence of the tricuspid valve is crucial for survival of children with hypoplastic left heart syndrome. We studied the morphology and topology of the valvar and subvalvar structures, trying to identify abnormalities which could impair valvar function.
A total of 82 specimens with hypoplastic left heart syndrome were examined pathologically. Measurements of valvar dimensions were taken, significant dysplasia of the valvar leaflets was noted and the muscular and tendinous supporting structures determined. The findings were correlated to the subgroups of hypoplastic left heart syndrome.
Of the hearts, 10 (12%) showed a bileaflet right atrioventricular valve, 27 (33%) a moderately and 2 (2%) a severely dysplastic tricuspid valve. The majority of the abnormalities was found in hearts with a patent mitral valve. In 79% of the hearts with mitral atresia, the septal surface was concave instead of convex to the right ventricular lumen and the direct tendinous attachments of the septal leaflet replaced by a multitude of freestanding papillary muscles. The number of direct septal attachments was significantly higher in hearts with a patent mitral valve.
The tricuspid valve in hypoplastic left heart syndrome can differ from the valve seen in normal patients. The subvalvar apparatus is different in hearts with mitral atresia, whereas dysplasia of the leaflets occurs more often together with mitral stenosis. These features should be considered in reconstructive operations as well as during diagnostic procedures.
Although the results of the modified Norwood procedure as palliation for the hypoplastic left heart syndrome have improved considerably, in-hospital mortality remains high (28% to 46%).
To establish the causes of death and consider their therapeutic applications, we reviewed our pathology experience from 1980 to 1995, inclusive, regarding 122 patients who died after undergoing the Norwood procedure.
The most important causes of death were found to be impairment of coronary perfusion (33 patients, 27%), excessive pulmonary blood flow (23 patients, 19%), obstruction of pulmonary arterial blood flow (21 patients, 17%), neoaortic obstruction (17 patients, 14%), right ventricular failure (16 patients, 13%), bleeding (9 patients, 7%), infection (6 patients, 5%), tricuspid or common atrioventricular valve dysfunction (6 patients, 5%), sudden death from presumed arrhythmias (6 patients, 5%), and necrotizing enterocolitis (3 patients, 3%). In 26 patients (21%), more than one factor appeared responsible for death.
The leading causes of death after the Norwood procedure were found to be largely correctable surgical technical problems associated with perfusion of the lungs (36%), of the myocardium (27%), and of the systemic organs (14%).
A neonate presented with an interrupted aortic arch type B and VSD with dysplastic aortic valve, subaortic stenosis, and aberrant right subclavian artery. We performed a direct anastomosis between the hypoplastic ascending aorta (0 3 mm), the main pulmonary artery and the descending aorta, mimicking a Norwood-type ventricular outlet. The right-ventricular outflow tract was reconstructed with a 8mm PTFE vascular graft. This combination of a modified Norwood with a Rastelli procedure facilitated establishment of a sufficiently large left-ventricular outflow tract via VSD, at the same time maintaining a biventricular system despite the coexisting anomalies.
Multiple obstructions in the left heart-aorta complex have been associated with poor survival. No consensus exists as to whether these patients will have a favorable outcome with biventricular repair where most advocate a univentricular approach.
Since late 1988, all 11 neonates seen with hypoplastic left heart complex, which includes aortic arch obstruction, underwent biventricular repair. All patients had antegrade aortic flow and no intrinsic aortic or mitral stenosis. Elimination of the extracardiac afterload was achieved by extensive ascending aorta and aortic arch reconstruction with a pulmonary homograft patch. All intracardiac shunts were eliminated to fully preload the left heart. The median age at first operation was 7 days and the mean weight, 3.59+/-0.49 kg. The echocardiographic variables used to evaluate the left heart-aorta complex were reviewed, and the preoperative and postoperative measurements were compared.
There were two early deaths. Four patients had six reoperations for left ventricular outflow tract obstruction, 2 of whom have required prosthetic valve replacement (1, aortic and mitral; 1, aortic), and 2 patients had three reoperations for recurrent coarctation. There was one late death at 3 years from pulmonary hypertension. Mean follow-up was 44+/-35 months. The 8 current survivors are all in New York Heart Association class I or II. The actuarial survival rate at 8 years is 63%, and the freedom from reoperation at 3 years is 25%.
We have successfully achieved biventricular repair in most of the patients with hypoplastic left heart complex, a subset of patients with hypoplastic left heart syndrome. Some growth of the left ventricular structures was already observed at the time of hospital discharge. However, reoperation, particularly for left ventricular outflow tract obstruction, appears likely. Increasing experience will more accurately define predictive criteria for the feasibility of biventricular repair.
A severely restrictive atrial septal defect (ASD) in neonates with hypoplastic left heart syndrome (HLHS) results in pulmonary venous hypertension, pulmonary edema, and intractable hypoxia. Between January 1983 and June 1998, 21 of 355 neonates presenting with HLHS (5.9%) underwent cardiac catheterization at median age 1 day (range 0 to 25), for creation or enlargement of a restrictive or absent interatrial communication. One patient died during preliminary angiography. Three underwent blade septostomy with 2 procedure-related deaths, and 1 had balloon atrial septostomy (BAS); all 4 died before surgical intervention. Fifteen underwent Brockenbrough atrial septoplasty with transatrial needle puncture and serial balloon dilations of the new ASD, 5 after unsuccessful BAS. The most recent patient had a stent placed across the atrial septum after transatrial needle puncture. In the 16 patients treated with septoplasty or stent, oxygen saturation increased from 50 +/- 4% to 83 +/- 2% (p <0.0001) and transatrial pressure gradient decreased from 16 +/- 1 to 6 +/- 1 mm Hg (p <0.0001). One patient died awaiting transplantation, supportive care only was requested in 1, and 14 underwent stage 1 palliation. Eight of 14 (57%) survived to hospital discharge. Six of 7 (86%) survived bidirectional Glenn and the 3 who have undergone fenestrated Fontan are alive. In neonates with HLHS, a restrictive ASD resulting in profound cyanosis demands urgent intervention. BAS is frequently unsuccessful and blade septostomy has high mortality. Pulmonary venous hypertension can be adequately relieved by Brockenbrough atrial septoplasty or stenting, allowing stabilization before reconstructive surgery or while awaiting transplant.
Results of Norwood's operation for lesions other
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