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-Basal CT indicates the dilated azygos vein (Av) that joins the superior vena cava (SCV) (a); contrast-enhanced MDCT scans obtained at the level of the diaphragmatic crus and the level of the azygos vein arch shows the enlarged azygos vein (Av) draining into the superior vena cava and dilated emiazygos vein draining into azygos vein (b and c). The IVC is not identified with the liver.
Source publication
Interruption of the inferior vena cava (IVC) with azygos continuation is a rare congenital anomaly, in which the IVC is interrupted below the hepatic vein and venous return beyond this point is restored by the dilated azygos and hemiazygos veins draining into the superior vena cava. A case of the interruption of the IVC with azygos/emyazygos contin...
Contexts in source publication
Context 1
... mass-like aspect at chest X-ray examination was due to abnormal enlargement of azygos vein (maximum caliber about 20 mm; the normal caliber is about 3-7 mm) caused by congenital absence of infrahepatic segment of IVC ( Figs. 2 a-c). The dilated hemiazygos vein (maximum caliber about 10 mm; the normal caliber is about 2-5 mm) and the azygos-hemiazygos junction is well observed in CE-MDCT axial images ( Fig. 2 b). ...
Context 2
... veins drained directly in right atrium, while right renal vein and IVC conducted their blood in azygos vein ( Figs. 2 a-c; Figs. 3 a-d). ...
Context 3
... mass-like aspect at chest X-ray examination was due to abnormal enlargement of azygos vein (maximum caliber about 20 mm; the normal caliber is about 3-7 mm) caused by congenital absence of infrahepatic segment of IVC ( Figs. 2 a-c). The dilated hemiazygos vein (maximum caliber about 10 mm; the normal caliber is about 2-5 mm) and the azygos-hemiazygos junction is well observed in CE-MDCT axial images ( Fig. 2 b). ...
Citations
... While IIVC typically does not exhibit symptoms, it has the potential to introduce complexities within the therapeutic context. 13 Instances of fortuitous venous thromboembolism (VTE) have been recorded, highlighting the potential prothrombotic hazards linked to this vascular anomaly. 14-20 ...
Objectives: This study aimed to comprehensively investigate the clinical manifestations and outcomes of prenatally diagnosed isolated interrupted inferior vena cava (IIVC) with azygos continuation to shed light on the significance of prenatal diagnosis. Methods: A longitudinal study involved 12 fetuses prenatally diagnosed with IIVC and azygos continuation. Detailed fetal anomaly scans and echocardiography were performed, and pediatric cardiologists confirmed postnatal diagnoses. Genetic testing and extensive follow-ups were also performed. Results: The study confirmed the high diagnostic accuracy of prenatal identification, with 100% postnatal confirmation. Most patients exhibited favorable outcomes, emphasizing the importance of prenatal diagnosis. Genetic testing revealed normal chromosomal arrangements in all tested cases. Conclusion: Our study underscores the vital role of prenatal diagnosis in managing isolated IIVC cases and highlights their generally favorable prognosis. This study contributes to understanding this rare vascular anomaly and its implications for clinical practice.
... ICV interruption with hemiazygos continuation is a benign condition and, in this case, as vascularization was well compensated, no treatment was needed. Otherwise, the knowledge of the condition was crucial for the patient in case of necessary surgical intervention (9). ...
Inferior vena cava (IVC) interruption with azygos/hemiazygos continuation is an extremely uncommon congenital vascular anomaly, which may present with multiple variants. As a result, it is challenging to find in the literature the same anatomical variant. We report a unique case of an interrupted IVC with hemiazygos and transhepatic continuation in an 83-year-old female patient. The case was evaluated by performing Computed Tomography (CT) as imaging modality, with a multiphase protocol, able to detect accurately this complex vascular anomaly. The purpose of this case report is not only to present this remarkable case but also to briefly show the types of interrupted IVC, starting from the anatomy and the embryology of the IVC and the azygos system, and to discuss the value of imaging in detecting the vascular anomaly.
... Classically associated with polysplenia, cardiovascular malformations, and situs anomalies [15]. ...
Congenital malformations of the inferior vena cava (IVC) are rare and often asymptomatic, typically discovered incidentally during imaging. However, these anomalies can result in circulatory stasis, impede venous return, and serve as predisposing factors for thrombus formation. Here, we present a unique case of a 28-year-old female patient who was found to have interrupted IVC with azygos continuation, an exceedingly rare IVC anomaly, during a work-up of extensive bilateral deep vein thrombosis (DVT) with an intraabdominal extension which was triggered by recent combined oral contraceptive pills (OCP) use. This case highlights the importance of considering vena cava malformations as an underlying cause for extensive DVT, even in the absence of conventional risk factors. Clinicians should be aware of the potential association between congenital vena cava anomalies and thrombotic events, as early recognition and appropriate management are crucial for preventing complications such as pulmonary embolism.
... Liu et al reported that the frequency of an absent IVC is 0.3% of the healthy population and 0.6% of the population with heart disease [7]. Some cases of absent IVC with azygos or hemi-azygos continuation have been reported [7][8][9]. However, these reported cases didn't accompany the malrotation of the digestive tract. ...
We present a case of intestinal malrotation with an absent inferior vena cava, which was found in a cadaver during a dissection course in our medical school. The intestinal malrotation was Amir–Jahed type 2, with the large intestine on the right side and the small intestine on the left side of the abdominal cavity. The descending colon was fixed on the right side of the posterior abdominal wall and continued into the pelvic cavity from the right side. The cadaver also had a venous system anomaly. The pre-renal segment of the inferior vena cava, which is a section between the renal vein and the hepatic vein, was absent. The inferior vena cava connected to the azygos vein after being joined by bilateral renal veins. The only hepatic segment of the inferior vena cava, which was posterior to the liver and received hepatic veins, penetrated the diaphragm and flowed into the right atrium. To our knowledge, this is the first report of these two anomalies appearing concurrently. We discuss the details of this case and the embryological considerations.
... We relatively agree with Mandato et al. [7], who stated that the interruption of the inferior vena cava (IVC) with azygos continuation is a rare congenital anomaly. In contrast, Aborashed et al. [8], reported that the azygos/ hemiazygos continuation percentage reaches 23.5% of the studied population. ...
Background
Anomalies of the thoracic systemic venous return vary widely and range from those with completely normal physiology to severe right to left shunting thus requiring surgical correction. The aim of the study is to enhance the awareness of multidetector computed tomography (MDCT) role in evaluation of systemic venous abnormalities, and be familiar with the imaging characteristics of even the extremely rare abnormalities.
Results
Among 270 examined patients, 15.19% had systemic venous abnormalities. Inferior vena cava (IVC) congenital anomalies accounted for (24.4%) of the detected abnormalities (prevalence: 3.7% among the studied population) where IVC interruption with azygos continuation was the most common detected IVC abnormality accounting for 17.7% of the detected abnormalities (prevalence: 2.6%), while IVC thrombosis accounted for 21.9% (prevalence: 3.3%). Persistent left sided superior vena cava (SVC) accounted for 14.6% of the detected abnormalities (prevalence: 2.2%), while SVC syndrome represented 19.5% (prevalence: 2.9%) and SVC aneurysm represented 2.4% (prevalence: 0.37%). Retroaortic brachiocephalic vein (BCV) and BCV thrombosis accounted for 7.3% each (prevalence: 1.1). Finally, persistent levo-atrial cardinal vein represented 2.4% of the detected abnormalities (prevalence: 0.37%).
Conclusions
MDCT is a non-invasive modality that can provide detailed information about the systemic thoracic veins before surgical or interventional procedures, especially in patients with congenital anomalies.
... 3 The prevalence of IVC anomalies ranges between 0.07%-8.7% in the general population, while the prevalence of azygos or hemiazygos continuation is about 1.5%. 4 These anomalies are usually asymptomatic, and usually diagnosed incidentally when imaging is performed for other reasons. 4 Acquaintance with these uncommon malformations and their diagnosis is important for two main reasons: First, familiarity with these anatomic variants can help to avoid misdiagnosis ...
... 4 These anomalies are usually asymptomatic, and usually diagnosed incidentally when imaging is performed for other reasons. 4 Acquaintance with these uncommon malformations and their diagnosis is important for two main reasons: First, familiarity with these anatomic variants can help to avoid misdiagnosis ...
... 3 In cases where an anomaly is accompanied by predominant venous drainage by the azygos route, intra-procedural preservation of the azygos is of paramount importance, since accidental ligation of this draining vein in these patients may lead to catastrophic results. 4 IVC interruption is regarded as a predisposing factor to the development of lower extremity DVT. 5 Moreover, it was observed that lower limb DVT is more common in males, and for the most part is proximal and bilateral. 6 Absence of IVC was estimated to be present in 5% of unprovoked DVT cases in young patients (age < 30 years). ...
A 22-year-old healthy man presented to the emergency department with worsening left flank and testicular pain. lower abdominal pain and lower urinary tract symptoms, were also noted.
Contrast-enhanced CT demonstrated several vascular malformations: both common iliac veins converging to an infra renal inferior vena cava (IVC) with an absent cephalad IVC. Multiple collateral veins were noted, and both the Azygos and Hemiazygos veins were seen dilated, serving as an alternative venous drainage path due to the interrupted IVC.
The patient’s CT was also notable for several pathologies: bilateral iliac vein thrombosis and left-sided testicular vein thrombus with surrounding fat stranding, suggestive of testicular vein thrombophlebitis.
The patient was admitted, and received antibiotic and anticoagulation treatment, with clinical improvement.
Hypercoagulability workup was obtained, and the patient was found to be heterozygous for Factor V Leiden.
Interrupted IVC with azygos continuation is an uncommon, and mostly a benign vascular malformation, resulting from abnormal development of IVC-contributing segments during embryogenesis. It is associated with lower limb deep vein thombosis and hyper-coagulable states. It is imperative for radiologists to be acquainted with this entity, in order to avoid misdiagnosis.
Testicular vein thrombosis is uncommon, mostly associated with prothrombotic disorders, and it should be considered when coagulopathy is suspected.
... 25,26 A study described a catastrophic event in a patient with an interruption of the hepatic segment of the IVC due to an accidental ligation of the azygos vein. 27 In unusual cases, associated pulmonary thromboembolism, thrombus in the right atrium, and IVC thrombosis have been observed in two women, one with dyspnea and one with sudden onset of back pain and swelling of the legs and thighs. Both received incidental diagnoses of an underlying interruption of the hepatic segment of the IVC. ...
Background/purpose
Inferior vena cava (IVC) interruption is rare and can be detected through prenatal or postnatal imaging. It usually occurs in patients with heterotaxy syndrome with bilateral left-sidedness (left isomerism or polysplenia syndrome), indicating a laterality defect. However, its long-term outcomes remain unclear.
Methods
This retrospective study included a patient cohort with evidence of IVC interruption based on imagining data (1980–2019) selected from our institutional database.
Results
We included 34 (male/female = 14/20) patients with IVC interruption. Most of the patients had left isomerism of the bronchopulmonary situs (96.4%) and cardiac atrial situs (90.3%). Splenic anomalies, including polysplenia (35.7%), lobulated spleen (39.3%), inversus solitary spleen (10.7%), and asplenia (3.6%), were common. Normal cardiac structure was noted in four (11.8%) patients. Congenital heart disease (CHD) was noted in 30 patients: 7 with simple CHD and 23 with severe CHD. Bradycardia occurred in 47.1% of the patients and was not associated with CHD. Splenic variations were not associated with CHD or bradycardia. The survival rates for the 10-, 20-, and 40-year age groups were 0.880, 0.792, and 0.441, respectively; severe CHD was the only risk factor.
Conclusion
IVC interruption can present as an isolated lesion and be associated with CHD. Although bradycardia was common among the patients, CHD severity was the only risk factor for survival. Patients with IVC interruption commonly have left isomerism at the atrial and bronchopulmonary situs, but the spectrum of splenic abnormalities is wide, including polysplenia, lobulated spleen, solitary inversus spleen, and, rarely, asplenia.
... The azygos and hemiazygos veins in this patient developed well because of interruption of the IVC with azygos and hemiazygos continuation. 10,11 However, when the authors placed a drainage cannula in the azygos vein, they feared the possibility of poor VV ECMO flow because the blood return in the azygos vein did not include that of the digestive organs. Therefore, they placed the tip of the multiport drainage cannula at the junction between the azygos vein and SVC to aspirate blood from both vessels (Fig 3, A). ...
An intracardiac left-to-right shunt increases pulmonary blood flow and pulmonary artery (PA) pressure (PAP), a condition that can cause pulmonary vascular injury and result in the development of Eisenmenger’s syndrome (ES) in the terminal stage. Moreover, the extreme increase in pulmonary blood flow and/or pulmonary vascular resistance (PVR) is associated with giant PA aneurysms (PAAs); however, these cases are rare. For patients with ES and giant PAA, heart–lung transplantation or, alternatively, bilateral lung transplantation (BLTx) combined with intracardiac repair and PA replacement are the only two available life-saving interventions. In patients with severe pulmonary arterial hypertension (PAH), PVR elevation, low systemic pressure, and high airway pressure should be avoided during anesthesia, as all these factors can induce right ventricular (RV) failure and create a lethal situation. Additionally, a giant PAA can sometimes compress the coronary arteries and airways, which can cause coronary ischemia and airway obstruction after anesthesia induction. In such cases, veno-arterial (V-A) extracorporeal membrane oxygenation (ECMO) is often used. However, when peripheral V-A ECMO is used in patients with narrowed peripheral arteries, the return flow can decrease and the mixing point of the patient’s arterial blood with the ECMO’s return flow can move to the distal portion of the aortic arch, a situation that can cause watershed phenomena and/or hypoxic encephalopathy (Harlequin syndrome). Herein, we report the management of BLTx in a patient with ES, severe PAH, giant PAA, constricted trachea and right bronchus, and interruption of the inferior vena cava (IVC) with azygos and hemiazygos continuation. As we believed that the constricted trachea and right bronchus could become obstructed and cause ventilation difficulties after general anesthesia induction, we had initially deemed it safer to use V-A ECMO for the patient. However, it would have been impossible to ensure sufficient V-A ECMO because of the patient’s narrowed axillary and femoral arteries. To solve these problems, a drainage cannula was placed in the azygos vein, a return cannula was placed in the right atrium (RA), and veno-venous (V-V) ECMO was established before induction of general anesthesia.
Although anesthesiologists pay great attention to severe PAH and hypoxemia caused by a right-to-left shunt during BLTx in ES patients, they should also pay attention to coexisting PAA, which can cause central airway obstruction (CAO). As this latter condition is exacerbated by the induction of general anesthesia, gas exchange should be secured during general anesthesia for patients with ES, PAA, and CAO. Although V-A ECMO is often chosen to maintain circulation and prevent hypoxemia in this circumstance, we selected V-V ECMO because our patient had right-to-left shunt, TR, and narrowed axillary and femoral arteries. Our case presents another ECMO option for patients with severe PAH and a right-to-left shunt. Additionally, because our patient also had interruption of the IVC with azygos and hemiazygos continuation, we placed an ECMO drainage cannula in the azygos vein, rather than in the IVC, which enabled us to establish V-V ECMO with sufficiently strong pump flow. This indicated that the azygos vein can be used as an alternative to the IVC for placement of a drainage cannula in patients with interruption of the IVC with azygos and hemiazygos continuation.
... In this condition, the IVC is interrupted below the hepatic vein and venous return beyond this point is re-established by the dilated azygos and hemiazygos veins draining into the superior vena cava (SVC). [1] Isolated congenital anomalies of IVC are rarely reported. The incidence of this anomaly approximates 0.6% in patients with congenital heart defects. ...
... As a result, blood shunts from the supra-subcardinal anastomosis through the mildly dilated retrocrural azygos vein. [1,5] Different percutaneous interventions in patients with IVC interruption have been described by various literatures. In this series of cases with interrupted IVC treated through various interventions, we like to highlight the challenges faced during procedures and our management methods. ...
Interruption of the inferior vena cava with azygos continuation is a rare congenital anomaly. This anomaly becomes clinically important during cardiac interventions.
... The prevalence of IBV developmental abnormalities in the general population ranges from 0.07% to 8.7% [1]. They are usually discovered during autopsies, but are increasingly found with the latest imaging techniques [2]. ...
... The prevalences of the duplication of the inferior vena cava, azygos continuation and retroaortic renal vein are respectively 0.2% -3%; 0.6% and 2.1%. The presence of such a combination of variations is very rare [1] [4]. In this observation the patient presents a complex variation of the IBV including: the hepatic, renal, sub-renal and ilio-cave segment. ...
... Recognition of IBV duplication is relevant in retroperitoneal surgery (especially thora-phreno-laparotomy) given the risk of massive per-operative hemorrhage in the event of unfamiliarity or vascular interventions, to avoid recurrent pulmonary embolism after the installation of a cave filter [1] [2] [3] [4]. ...
