CT findings of an incidental segmental aplasia of the caudal vena cava with azygos continuation in a guinea pig (Cavia porcellus).

Background: Segmental aplasia of the caudal vena cava (CVC) with azygos continuation is a congenital malformation macroscopically described in mammals including humans, dogs, and rodents. It is usually detected as an incidental finding and the final diagnosis is reached by computed tomography (CT), fluoroscopy, or post-mortem dissection. Case Description: A 3-year-old guinea pig (Cavia porcellus) presented with subacute dyspnea. A computed tomographic examination was performed for the evaluation of subtle pulmonary changes previously suspected on conventional radiography, and a segmental aplasia of the CVC with azygos continuation was identified as an incidental finding. Conclusion: According to database negative results, this is the first report describing a segmental aplasia of the CVC and azygos continuation in a guinea pig by CT.

A cadaver study evaluating intraluminal anomalies of the left common iliac vein.

OBJECTIVE: Intraluminal anomalies within the left common iliac vein, characteristic of iliac vein compression syndrome, are thought to result from compression by and pulsation of the overlying right common iliac artery. This cadaver study was designed to expand on the existing literature by surveying and photographing these spurs in addition to exploring whether certain factors, inherent to the cadaver, are associated with spur presence. METHODS: Dissection to expose the aorta, inferior vena cava, and common iliac arteries and veins was performed in 51 cadavers. The spinal level at which the iliac vein confluence occurred was noted. The point at which the right common iliac artery crossed the left common iliac vein was examined for plaque presence. The overlying arterial structures were then transected to expose the venous system. The inferior vena cava was incised to facilitate observation into the mouth and full extent of the left common iliac vein. Spurs were photographed and documented. Statistical analysis was conducted to determine whether sex, body mass index (BMI), plaque presence, or level of the iliac vein confluence are associated with spur presence. RESULTS: Spurs within the left common iliac vein were observed in 16 of 51 cadavers (31.4%). All spurs were located at the point that the right common iliac artery crossed the left common iliac vein. Using1 the classification system established by McMurrich, 67% of spurs (n = 10) were marginal and triangular; 25% (n = 4) were columnar. One marginal, linear spur (6%) and one partially obstructed spur with multiple synechiae (6%) were observed. Among this population, males were 73% less likely to have a spur (odds ratio, 0.269; P = .041). No significant relationship was found between plaque presence and spur presence (odds ratio, 0.933; P = .824) and no significant differences were noted between BMI and spur presence (χ2 = 1.752, P = .625). Last, a significantly greater percent of spurs was found within cadavers with an iliac vein confluence located at the L5/S1 disc space (χ2 = 9.650; P = .002). CONCLUSIONS: Study findings show that spurs are more common when the confluence of the common iliac veins occurs at a lower spinal level. The level of the iliac vein confluence may be important in identifying patients at increased risk of venous disease. The findings also suggest that plaque within the right common iliac artery and BMI display no distinct relationship with spur presence. Further investigation is needed to understand exactly what factors lead to spur formation.

STIC-HD live flow technology in the antenatal diagnosis of scimitar syndrome: A case report.

Scimitar syndrome (SS) is a rare entity with an incidence of approximately 1-3 in 200 000 people. It is typically characterized by complete or partial anomalous pulmonary venous drainage from the right lung into the systemic venous circulation, most commonly the inferior vena cava (IVC). For the first time, we report the diagnosis of SS in a fetus in utero using four-dimensional (4D) spatiotemporal image correlation combined with high-definition live flow rendering mode (STIC-HD live flow).

Interrupted inferior vena cava draining into the coronary sinus associated with circumflex artery to coronary sinus fistula.

In an adult patient, coronary artery fistula involving the circumflex artery (CX) connected to the coronary sinus caused aneurysm of the left main and CX associated with ectasia of the intermediate branch. The patient had posterolateral infarction with severe ischemic mitral regurgitation and moderate tricuspid regurgitation. A rare venous return anomaly was also present. The inferior vena cava, which was interrupted at the level of the liver, continued with the hemiazygos to drain into a persistent left superior vena cava, which in turn drained into the coronary sinus. Surgery included CX closure and mitral and tricuspid repair. The strategy had to be adapted to the anatomy. The fistula was dissected and snared for cardioplegia delivery, and venous return was achieved by cannulation of the superior vena cava and femoral vein. The procedure was uneventful, and 4 years later the patient is asymptomatic.

A remarkable case report of an interrupted inferior vena cava with hemiazygos and transhepatic continuation.

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.

Direct Oral Anticoagulants for Inferior Vena Cava Agenesis.

Deep vein thrombosis (DVT) is common in the general population, with an annual incidence of 1 to 2 per 1000 people. Inferior vena cava agenesis (IVCA) increased the risk of developing DVT and is found in approximately 5% of young adults (20-40-year-olds) diagnosed with unprovoked proximal DVT. IVCA can be caused by a defective embryological process, or be a result of intrauterine or perinatal thrombosis. Its estimated incidence in the general population ranges from 0.0005% to 1%, usually involving a partial absence of one of the four segments of the inferior vena cava (IVC). The management during the extended phase of patients with DVT associated with IVCA is not yet harmonized, as it is poorly described in the literature. Patients with IVCA are considered to be at high risk of DVT occurrence, prompting physicians to continue extended anticoagulation, often using vitamin K antagonists. In this retrospective study, we present a cohort of 11 patients diagnosed with IVCA following a DVT, who subsequently received extended treatment with a direct oral anticoagulants. These findings offer reassuring insights into the extended utilization of direct oral anticoagulants, demonstrating both antithrombotic efficacy and a favorable safety profile.

Orthostatic proteinuria due to inferior vena cava interruption without nutcracker phenomenon in an old obese female: a case report and literature review.

BACKGROUND: Nutcracker syndrome (NCS) caused by left renal vein (LRV) entrapment, is one of the most common causes of orthostatic proteinuria. In stereotype, orthostatic proteinuria is often accompanied by left renal vein obstruction and is found in young and underweight individuals. Here, we report a rare case with orthostatic proteinuria in an old obese female caused by a rare type of congenital inferior vena cava (IVC) interruption. CASE PRESENTATION: A 65-year-old obese woman, who suffered from fluctuated proteinuria, had been misdiagnosed as chronic glomerulitis for 30 years. Instead of having any sign of NCS, she had a unique type of IVC interruption. Most venous blood from infrarenal IVC and right kidney drained into her LRV, and then through the expanded communicating vessel, drained into the left ascending lumbar vein which extended as hemiazygos vein. To the best of our knowledge, this is one of the first cases reported of orthostatic proteinuria attributed to the subsequent hemodynamic irregularity caused by IVC interruption without nutcracker phenomenon. CONCLUSION: Adult-onset orthostatic proteinuria is relatively rare, hard to be recognized and could be misdiagnosed as chronic glomerulonephritis. The case provided a novel differential diagnostic condition for those who suffered from fluctuated proteinuria of unknown causes.

RESULTS OF TREATMENT OF DEEP VEINS THROMBOSIS IN PATIENTS WITH CONGENITAL ANOMALIES OF THE INFERIOR VENA CAVA.

Features of treatment of venous thromboembolism in patients with abnormalities in the development of the inferior vena cava. Congenital anomalies of IVC development are a rather rare pathology. The analysis of treatment results will better understand the pathophysiology of the disease and form an optimal treatment strategy. We analyzed the results of treatment of 1243 patients with venous thromboembolism from 2010 to 2022. Congenital anomalies of inferior vena cava(IVC) development were diagnosed in 2 (0.16%) patients. One patient had IVC aplasia, the other had IVC hypoplasia. Both patients had bilateral iliofemoral deep vein thrombosis(DVT). For the treatment of patients, we used anticoagulant therapy and elastic compression of the lower extremities. During the study period, venous thromboembolic complications in the form of pulmonary embolism were not recorded, fatal complications were not diagnosed. Thus, the results of treatment of patients with venous thromboembolism and anomalies in the development of IVC suggest that the use of anticoagulant therapy in this category of patients allows to obtain positive results of treatment.

Bilateral inferior venae cava combined with the persistent left superior vena cava and hemiazygos continuation of left inferior vena cava with drainage into right atrium: A case report.

The persistent left superior vena cava (PLSVC) is a common venous abnormality. However, malformation of the bilateral inferior venae cava (IVC) is extremely rare, with an incidence rate of .3%. IVC malformation is associated most frequently with heart defects and isomerism and often has a poor prognosis. We presented a case of vascular malformations in the fetus of bilateral caval veins with the interruption of the left-sided venous return with hemiazygos continuation in presence of a right-sided inferior caval vein. Also noted were the PLSVC and a dilated right heart with a widened pulmonary trunk. In this case, there were no heart defects or chromosomal abnormalities, and the newborn postpartum was in a good condition.

Unique case of pelvic congestion syndrome caused by a new communication branch of the portal-vena cava system.

Congenital portosystemic shunt (CPS) is a developmental anomaly of the portal vein system. The disease can cause blood from the portal vein to flow into the vena cava, resulting in various atypical clinical manifestations. Pelvic congestion syndrome (PCS) caused by CPS is particularly rare. A young woman with PCS had an abnormal communicating branch of the left ovarian vein (OV). Her left OV drained normally into the left renal vein, and at the same time communicated with the portal vein, forming an extrahepatic portosystemic shunt. With embolization of her left OV, the patient was cured of PCS.

A repeatable CT protocol for quantifying caudal vena cava growth in medium and large breed dogs.

Developmental malformations can cause stunted or abnormal growth and clinical disease in dogs. In humans, measurements of the inferior vena cava are used as methods for detecting abnormal growth trajectories. The objectives of this retrospective, multicenter, analytical, cross-sectional study were to develop a repeatable protocol to measure the caudal vena cava (CVC) and generate growth curves in medium and large-breed dogs during development. Contrast-enhanced CT DICOM images from 438 normal dogs, aged from 1 to 18 months, from five specific breeds were included. A "best guess" measurement protocol was created. Dogs were stratified into medium or large breed groups based on growth rate trajectories. Linear regression models and logarithmic trend lines were used to evaluate the CVC growth over time. The CVC measurements were analyzed from four anatomical regions: thorax, diaphragm, intra-hepatic, and renal. The thoracic segment produced the most repeatable measurements with the highest explanatory power. The CVC thoracic circumference ranged from 2.5 to 4.9 cm from 1 to 18 months of age. Medium and large breeds had similar CVC growth trajectories, with comparable estimated marginal means, however medium dogs reached 80% of predicted final CVC size approximately 4 weeks earlier than large breed dogs. This new protocol provides a standardized technique for evaluation of the CVC circumference over time using contrast-enhanced CT and is most repeatable when taken at the thoracic level. This approach could be adapted for other vessels to predict their growth trajectories, generating healthy reference population data for comparison against patients with vascular anomalies.

Venous Ulcer in a 5-Year-Old Girl.

BACKGROUND: Agenesis of the inferior vena cava (IVC) is an extremely rare congenital malformation. Although IVC dysplasia can present with symptoms, because of the low prevalence of this disease, it is often omitted from routine examination. Most reports on this topic have described the absence of the IVC; the absence of both a deep venous system and the IVC is even rarer. Chronic venous hypertension and varicosities leading to venous ulcers have been reported in patients with absent IVC that could be surgically bypassed; however, the absence of iliofemoral veins precluded any bypass procedure in the present patient. CASE PRESENTATION: The authors report a case of IVC below renal vein hypoplasia in a 5-year-old girl who presented bilaterally with venous stasis dermatitis and ulcers in the lower extremity limb area. Ultrasonography revealed no clear IVC and iliofemoral venous system under the renal venous plane. Magnetic resonance venography subsequently confirmed the same findings. The patient's ulcers were healed by compression therapy and routine wound care. CONCLUSIONS: This is a rare case of venous ulcer in a pediatric patient stemming from congenital IVC malformation. With this case, the authors demonstrate the etiology of the appearance of venous ulcers in children.

Atrial fibrillation ablation in a single atrium with inferior vena cava interruption.

Common atrium (CA), also called three-chambered heart, is one of the rare congenital anomalies, defined by a complete absence of the atrial septum, eventually associated with malformation of the atrioventricular (AV) valves. We report the case of a 57-year-old woman with CA complicated with Eisenmenger syndrome and inferior vena cava interruption, who suffered from symptomatic persistent atrial fibrillation (AF). She underwent an initial successful pulmonary vein isolation procedure. A repeat procedure for perivalvular atrial flutter was complicated with inadvertent complete AV block, due to unusual AV node location in this challenging anatomy.

Conduta obstétrica em caso de hipoplasia materna da veia cava inferior / Obstetric management in case of the maternal inferior vena cava hypoplasia

A hipoplasia da veia cava inferior é uma patologia rara que integra o conjunto de anomalias do desenvolvimento da veia cava inferior. A sua incidência situa-se entre 0,3%-0,5% na população saudável e 5% nos adultos jovens sem fatores de risco para trombose venosa profunda, sendo considerada um importante fator de risco para o desenvolvimento de trombose dos membros inferiores. O principal objetivo deste trabalho é reportar a conduta obstétrica de um caso clínico de uma grávida diagnosticada com hipoplasia da veia cava inferior, prévia à gravidez. Trata-se de um caso clínico, de uma grávida, primigesta, com 37 anos, com hipoplasia da veia cava inferior e heterozigotia para o gene MTHFR677 diagnosticadas, na sequência de uma trombose venosa bilateral dos membros inferiores e do segmento infrarrenal da veia cava inferior. A gravidez foi seguida em consulta hospitalar na nossa instituição, tendo a grávida sido medicada com enoxaparina em dose profilática e ácido acetilsalicílico, com um período pré natal que decorreu sem intercorrências. Às 37 semanas e 6 dias de gestação, deu entrada no Serviço de Urgência de Obstetrícia por rotura prematura de membranas. Intraparto foram utilizadas meias de compressão pneumática intermitente, tendo o parto ocorrido às 38 semanas de gestação por via vaginal (parto eutócico), do qual nasceu um recém-nascido do sexo feminino, com 2620g e índice de Apgar 9/10/10. O presente caso clínico demonstra que em situações de hipoplasia da veia cava inferior com um seguimento obstétrico adequado é possível a realização de um parto vaginal, possibilitando um desfecho obstétrico favorável (AU).

Hypoplasia of the inferior vena cava is a rare condition that belongs to the group of developmental anomalies of the inferior vena cava. It has an incidence between 0.3% and 0.5% in the healthy population and 5% in young adults without risk factors for deep venous thrombosis, being considered an important risk factor for the development of lower limb thrombosis. This study aims to report the obstetric conduct of a clinical case of a pregnant woman diagnosed with hypoplasia of the inferior vena cava prior to pregnancy. This is a clinical case of a pregnant woman, primigravid 37 years old, with hypoplasia of the inferior vena cava and heterozygosity for MTHFR677, diagnosed following a bilateral venous thrombosis of the lower limbs and the infrarenal segment of the inferior vena cava. The pregnancy was followed up in our institution. The pregnant woman was medicated with a prophylatic dose of low molecular weight heparin and acetylsalicylic acid with an uneventful prenatal period. At 37 weeks and 6 days of gestation, she was admitted to the Obstetrics Emergency Service due to premature rupture of membranes. Intermittent pneumatic compression sockings were used intrapartum, and at 38 weeks of gestation, a female newborn was vaginally delivered (eutocic delivery) with 2620g and an Apgar score of 9/10/10. The present clinical case demonstrates that in situations of hypoplasia of the inferior vena cava with an adequate obstetric follow-up, it is possible to perform a vaginal delivery, enabling a favourable obstetric outcome (AU).

Successful Completion of Left Laparoendoscopic Single-Site Donor Nephrectomy in a Patient with Duplicated Inferior Vena Cava: Case Report and Review of Literature.

Duplication of the inferior vena cava is a rare vascular anomaly that increases the complexity of living donor nephrectomy and subsequent transplant. We present the case of a successful left-side laparoendoscopic single-site donor nephrectomy performed in a donor with a duplicated inferior vena cava. The length of the left renal vein was adequate for anastomosis in the recipient, with no late surgical complications at 9 months for both donor and recipient. Duplicated inferior vena cava is not a contraindication for left kidney transplant. Preoperative assessment and planning with computed tomography angiography are essential. Laparoendoscopic single-site donor nephrectomy can be performed safely in patients with duplicated inferior vena cava.

Venous Thromboembolism in a Patient with Interrupted Inferior Vena Cava and Compressed Azygos Continuation: A Case Report and Review of Literature.

We report an unusual case of a 40-year-old male patient who experienced painful swelling of the left lower limb that persisted for 1 week. Imaging modalities not only confirmed the diagnosis of acute iliofemoral venous thrombosis and pulmonary embolism (PE), but also an incidental finding of interrupted inferior vena cava (IVC). This congenital anomaly is uncommon but rarely associated with venous thromboembolism (VTE). The azygos continuation was compressed by the descending aorta against the 11th thoracic vertebrae, which was identified as the cause of VTE. He was treated successfully with anticoagulation and compression therapy. The patient was discharged with lifelong oral Rivaroxaban and remained asymptomatic. In the literature, only 9 cases of interrupted IVC-associated PE were identified but none was due to significant venous compression.

Inferior Vena Cava agenesis presenting as deep vein thrombosis in an eight year-old girl.

Agenesis of vena cava inferior (AVCI) is a rare congenital malformation with a prevalence of 0.0005-1% in the general population. High level of suspicion is required in young patients with deep vein thrombosis (DVT), particularly bilateral. We present an 8-year-old girl with AVCI presenting as bilateral lower extremity DVT and a review of the literature in pediatric cases with AVCI and DVT.

Computed tomography and magnetic resonance imaging of congenital thoracic systemic venous anomalies.

We present the imaging findings of thoracic systemic venous anomalies diagnosed by computed tomography and magnetic resonance imaging. Persistent left superior vena cava is the commonest anomaly of the thoracic systemic veins encountered either incidentally as an isolated finding or associated with congenital heart disease. Inferior vena cava (IVC) interruption with azygos continuation is the second most common anomaly, which may also be isolated or be associated with left isomerism syndrome. The article will also discuss other rarer systemic venous anomalies including retroaortic brachiocephalic vein and IVC drainage into the left atrium. Finally, the impact of pre-procedure reporting of thoracic systemic venous anomalies on the choice of intervention and patient outcome will be addressed.

Intra-abdominal haemorrhaging after cardiac catheterisation: the importance of recognising vascular anomalies in heterotaxy syndrome.

A 2-month-old boy with a single ventricle underwent cardiac catheterisation. Inferior vena cava angiography at the end of the examination revealed local stenosis, flexion, and connection to the right hepatic vein. Six hours after catheterisation, he went into haemorrhagic shock. CT revealed contrast extravasation into the liver with ascites. A precise diagnosis of vascular anomalies is mandatory, especially in patients with heterotaxy syndrome.