Figure 3 - uploaded by Puwadon Thitivaraporn
Content may be subject to copyright.
Source publication
Objectives
Valved homografts are commonly used for right ventricular outflow tract reconstruction. However, despite good early results, they lack durability. This study was designed to compare single-center results of implantation of 3 types of right ventricular outflow tract conduit, in terms of patient survival, graft failure, reoperation, and ri...
Context in source publication
Context 1
... was no significant difference in graft failure rates among the 3 grafts (p ¼ 0.48). Freedom from graft failure is shown in Figure 3. Freedom from reoperation at 2, 5, 10 years was 94.4%, 94.4%, 85.8% in pulmonic homograft group, and 97.3%, 95.4%, 74.9% in the aortic homograft group, respectively. ...
Citations
... One of the most widely accepted risk factors for failure is conduit size, with smaller conduits having more rapid degeneration. Junnil et al. [24] found in a study of 143 patients that conduit size < 18 mm diameter was a significant risk factor for reoperation, with many other studies showing a similar effect [25][26][27]. Patient age has also been found to significantly influence homograft durability, with younger patient age being a risk factor for early conduit failure [25][26][27]. ...
... Patient age has also been found to significantly influence homograft durability, with younger patient age being a risk factor for early conduit failure [25][26][27]. The comparison of long-term durability between aortic and pulmonary homografts has led to disparate results, with some centers reporting no significant differences [24] and others reporting superiority of pulmonary homografts [28,29], particularly in the infant population. Finally, the baseline patient anatomy may also influence long-term durability. ...
The need for right ventricular outflow tract reconstruction is common and growing in congenital heart surgery given expanding indications for the repair of congenital as well as acquired heart disease. Various valved conduit options currently exist including homografts, xenograft pulmonary valved conduits (Contegra™), and porcine valved conduits. The major limitation for all conduits is implant durability, which requires reoperation. Currently, cryopreserved homografts are often used given their superiority shown in long-term data. Significant limitations remain in the cost and availability of the graft, particularly for smaller sizes. Contegra conduits are available in a variety of sizes. Nonetheless, the data regarding long-term durability are less robust and studies comparing durability with homografts have been conflicting. Additionally, there is concern for increased rates of late endocarditis in this conduit. Porcine valved conduits offer a reliable option but are limited by structural valve degeneration associated with all types of bioprosthetic heart valve replacements. New developments in the field of tissue engineering have produced promising bio-restorative valved conduits that may overcome many of the limitations of previous conduit technologies. These remain in the early stages of clinical testing. This review summarizes the clinical data surrounding the conduits used most commonly in clinical practice today and explores emerging technologies that may bring us closer to developing the ideal conduit.
... A few studies [20][21][22][23] compared pulmonary and aortic homograft in terms of reintervention-free and overall survival. Their results suggested that pulmonary homograft use was associated with better reintervention-free and overall survival compared to aortic homograft. ...
Objectives
Since the introduction of surgical implantation of conduit for right ventricle-to-pulmonary artery pathway reconstruction, there has been a number of studies on possible factors which might potentially affect conduit longevity, as well as patient’s reintervention-free and overall survival. Still, no definite consensual agreement could be made thus far. We aimed to compare conduit longevity, reintervention-free survival, and overall survival between patients with congenital heart diseases indicated for operations involving right ventricle-to-pulmonary artery pathway reconstruction whose conduits were placed heterotopically to those with orthotopically placed ones.
Materials and methods
We retrospectively collected data from electronic medical records of Ramathibodi hospital from 1st January 2005 to 31st December 2022. Patients with congenital heart diseases whose operations involved reconstruction of right ventricle-to-pulmonary artery continuity were included. Patients whose medical record data were significantly missing were excluded. Demographic data, operative, and postoperative details were collected and reviewed.
Results
There were 67 patients included in our study, with 25 receiving orthotopic and the other 42 receiving heterotopic conduit implantation. Conduit dysfunction-free, reintervention-free, and overall survival were not statistically different between both groups. There was 1 early and no late death up to the end date of our study.
Conclusions
Conduits placed on a heterotopic position did not result in worse longevity, reintervention-free survival, as well as overall survival when compared to conduits placed on an orthotopic position. This suggested that the less technically demanding heterotopic conduit placement could be recommended as an operation of choice for right ventricular outflow tract reconstruction.
... This is consistent with studies from other groups that demonstrated small conduits as an independent risk for conduit re-operation. 2,4,6,7 Other risk factors for Original Article SMJ re-operation include younger age and diagnosis of truncus arteriosus in other studies 4,8 failing to achieve statistical significance in our multivariate analysis. The diagnosis of truncus arteriosus and younger age at conduit placement could easily confound the outcomes as both almost always need small conduits. ...
Objective: Our aim was to report on the long-term outcomes of patients who underwent RV-PA conduit placement at our institute. Materials and Methods: We retrospectively reviewed 407 RV-PA conduit placements from January 1997 to December 2018. The primary outcomes were freedom from and risk factor(s) for conduit re-operation. The secondary outcomes were survival, freedom from conduit dysfunction and conduit-related catheter intervention. Results: Of all the included patients, 209 were male (51.4%) and the median age at the operation was nine years (IQR 6, 18 years). The most commonly used conduit types were bovine jugular vein conduit (125, 30.7%), pulmonary homograft (122, 30.0%), and aortic homograft (76, 18.7%). The median follow-up time was 5.1 years (IQR 0.9, 9.2 years). The overall survival was 92.2% at 5 years. Freedom from re-operation was 95.4% and 84.2%, at 5 and 10 years. Factors related to conduit reoperation were age at operation less than 1 year, diagnosis rather than pulmonary atresia or stenosis, conduit size less than 18 mm, and conduit z-score greater than 3 (all p<0.01). In multivariate analysis, a significant contributing factor for re-operation was small conduit size (13 mm or smaller; HR 6.87 (95%CI 2.36, 20.01); p<0.001, 14–17 mm; HR 3.20 (95%CI 1.28, 8.00); p=0.013). Freedom from conduit dysfunction was 84.4% and 61.6% at 5 and 10 years. Freedom from conduit intervention was 94.4% and 89.3% at 5 and 10 years. Conclusion: Our study showed that patients had excellent survival with acceptable freedom from re-operation despite deteriorated conduit function. Small conduit size is associated with re-operation.
... Furthermore, not only conduit position but also conduit types and sizes could impact their durability and patient's reintervention-free and overall survival 5,8,9,[12][13][14][16][17][18] . However, most of the results contradicted each other, with no clear consensus made. ...
Objectives
Since the introduction of surgical implantation of conduit for right ventricle-to-pulmonary artery pathway reconstruction, there has been a number of studies on possible factors which might potentially affect conduit longevity, as well as patient’s reintervention-free and overall survival. Still, no definite consensual agreement could be made thus far. We aimed to compare conduit longevity, reintervention-free survival, and overall survival between patients with congenital heart diseases indicated for operations involving right ventricle-to-pulmonary artery pathway reconstruction whose conduits were placed heterotopically to those with orthotopically placed ones.
Materials and Methods
We retrospectively collected data from electronic medical records of Ramathibodi hospital from 1st January 2005 to 31st December 2022. Patients with congenital heart diseases whose operations involved reconstruction of right ventricle-to-pulmonary artery continuity were included. Patients whose medical record data were significantly missing were excluded. Demographic data, operative, and postoperative details were collected and reviewed.
Results
There were 67 patients included in our study, with 25 receiving orthotopic and the other 42 receiving heterotopic conduit implantation. Conduit dysfunction-free, reintervention-free, and overall survival were not statistically different between both groups. There were no deaths up to the end date of our study.
Conclusions
Conduits placed on a heterotopic position did not result in worse longevity, reintervention-free survival, as well as overall survival when compared to conduits placed on an orthotopic position. This suggested that the less technically demanding heterotopic conduit placement could be recommended as an operation of choice for right ventricular outflow tract reconstruction.
... Additionally, a study comparing mechanical valve replacement versus human tissue allografts showed children with allograft valves have longer survival and freedom from valve-related complications compared to children after mechanical valve placement in the aortic position (Lupinetti et al. 1999). Nevertheless, early failures of allograft valves within less than 10 years have been attributed to structural degeneration, immunologic responses and loss of cellular viability and valve growth capacity (Takkenberg et al. 2002), (Junnil et al. 2021). Autograft failure due to dilation of the valve instead of growth due to the increased mechanical stress at the aortic position compared to the pulmonary position has been reported (Etnel et al. 2018). ...
Valvular heart disease affects 30% of the new-borns with congenital heart disease. Valve replacement of semilunar valves by mechanical, bioprosthetic or donor allograft valves is the main treatment approach. However, none of the replacements provides a viable valve that can grow and/or adapt with the growth of the child leading to re-operation throughout life. In this study, we review the impact of donor valve preservation on moving towards a more viable valve alternative for valve replacements in children or young adults.
... Moreover, the limited availability of homografts in small sizes has restricted their extensive use in young patients, especially in infants. Contegra is widely used for patients of all ages, especially infants (22). However, studies have shown a high rate of postoperative endocarditis and conduit failure with Contegra(7, 23). ...
Background
Various conduits for right ventricular outflow tract reconstruction (RVOTR) have been reported but most of them are not available in China. We developed a simple handsewn valved conduit using expanded polytetrafluoroethylene (ePTFE). This study evaluated the mid-term outcomes for this conduit.
Methods
This retrospective study included a total of 72 patients who underwent RVOTR with ePTFE valved conduits between January 2014 and June 2020. During follow-up, echocardiograms were performed for all patients and magnetic resonance imaging for patients with repaired Fallot.
Results
Patients had a median age of 69 (interquartile range, 28-127) months and a median follow-up period of 33 (interquartile range, 9-51) months . There was no early death , but two late deaths (2.78%) occurred. The median conduit size was 18 mm (interquartile range, 18-20) and Z score was +1.3 (interquartile range, +0.6-+2). Peak velocity across the ePTFE valve was 2.38 m/s (95% confidence interval, 2.11 – 2.63 m/s). Pulmonary valve regurgitation was none or trivial in 27 (38.5%) patients, mild in 42 (60.0%) patients and moderate in one (1.4%) patient. Conduit dysfunction occurred in five patients: four developed moderate conduit stenosis and one moderate regurgitation. The right ventricular end diastolic volume index in repaired Fallot was significantly decreased after surgery(171 ml/m2 vs 130 ml/m2, P<0.001).No reintervention or conduit replacement was needed.
Conclusions
The handsewn ePTFE valved conduit we developed has appreciable hemodynamic outcomes during the mid-term follow-up period. Long-term follow-up studies are needed to corroborate our findings.
... The results of retrospective clinical studies are controversial. Some studies do not show significant differences (46,47), while other studies have shown that the survival rate of pulmonary valved conduit is higher than that of aortic valved conduit (48,49). ...
Valved conduits often correct the blood flow of congenital heart disease by connecting the right ventricle to the pulmonary artery (RV-PA). The homograft valved conduit was invented in the 1960s, but its wide application is limited due to the lack of effective sterilization and preservation methods. Modern cryopreservation prolongs the preservation time of homograft valved conduit, which makes it become the most important treatment at present, and is widely used in Ross and other operations. However, homograft valved conduit has limited biocompatibility and durability and lacks any additional growth capacity. Therefore, decellularized valved conduit has been proposed as an effective improved method, which can reduce immune response and calcification, and has potential growth ability. In addition, as a possible substitute, commercial xenograft valved conduit has certain advantages in clinical application, and tissue engineering artificial valved conduit needs to be further studied.
