Inferior vena cava agenesis and deep vein thrombosis: 10 patients and review of the literature

Venous recanalisation in the setting of post-thrombotic syndrome: An expert consensus from the French Society of Vascular Medicine (SFMV) and the French Society of Cardiovascular Imaging and Interventional Radiology (SFICV)

Several aspects of the management of post-thrombotic syndrome (PTS) are still a matter of debate, or not yet addressed in international guidelines. The objective of this expert consensus from the French Society of Vascular Medicine (SFMV) and the French Society of Cardiovascular Imaging (SFICV) was to define the main elements of diagnosis and treatment of this syndrome, and to develop a proposal for its preoperative, procedural and follow-up management. In this consensus, the following issues were addressed: clinical and ultrasound diagnosis; pre-procedural workup; indications and contraindications to venous recanalisation; procedures; clinical and duplex ultrasound reports; follow-up; long-term treatment; management of great saphenous vein incompetency; anticoagulant and antiplatelet therapy after venous stenting.

Thrombotic risk and features of patients with inferior vena cava agenesis: a multicentre, retrospective, observational study

BACKGROUND

Inferior vena cava agenesis (IVCA) is a rare anomaly predisposing affected people to lower-limb venous thrombosis with low frequency of pulmonary embolism. Antenatal thrombosis and inherited thrombophilia have been suggested as causes of IVCA. However, there is little evidence on the clinical course and management of this condition. We designed a patient registry to assess the thrombotic risk and features of IVCA.

METHODS

In this this multicentre, retrospective, observational study, we included patients with IVCA diagnosed by routine imaging from 20 hospitals in Spain (n=18), Portugal (n=1), and Italy (n=1). Patients were identified from a systematic search in radiology databases using data extraction software (cohort A) and alternative searches in medical records for confirmed IVCA (cohort B; option allowed when systematic approaches were unapplicable). Primary outcomes were clinical and imaging features, thrombotic risk, phenotype of IVCA-associated thrombosis, anticoagulant treatment, and the results of thrombophilia testing.

FINDINGS

We included patients with IVCA diagnosed by routine imaging studies done between Jan 1, 2010, and Dec 31, 2022. In the systematic search, 4 341 333 imaging exams were screened from the radiology databases of eight centres. 122 eligible patients were enrolled in cohort A. A further 95 patients were identified by screening medical records at 12 centres, of whom 88 were eligible and included in cohort B, making a combined cohort of 210 patients. 96 (46%) of 210 patients were female and 200 (95%) were European or Hispanic. 60 (29%) of 210 patients had hepatic IVC interruption, whereas 150 (71%) had extrahepatic IVCA. In cohort A, 65 (53%) of 122 patients had venous thrombosis, with an estimated annual risk of 1·15% (95% CI 0·89-1·46). Extrahepatic IVCA was associated with a greater risk of venous thrombosis than hepatic IVCA (56 [67%] of 84 patients vs nine [24%] of 38 patients, odds ratio 5·31, 95% CI 2·27-12·43; p<0·0001). Analysis of 126 patients with venous thrombosis pooled from cohorts A and B showed early-onset (median age 34·6 years, IQR 23·3-54·3) and recurrent events (50 [40%] of 126 patients). Patients with extrahepatic IVCA had greater proportions of lower-limb venous thrombosis (95 [87%] of 109 vs nine [53%] of 17, p=0·0010) and recurrence (48 [44%] of 109 vs two [12%] of 17, p=0·015), but lower rates of pulmonary embolism (10 [10%] of 99 vs four [33%] of 12, p=0·044) than did patients with hepatic IVCA. 77 (63%) of 122 patients with thrombosis underwent indefinite anticoagulation. 32 (29%) of 111 patients (29 [34%] of 86 with thrombosis) had coexisting thrombophilias. The recurrence risk was lower for patients receiving indefinite anticoagulation (adjusted odds ratio 0·24, 95% CI 0·08-0·61; p=0·010), and greater for thrombophilias (3·19, 1·09-9·32; p=0·034).

INTERPRETATION

This evaluation of a large patient cohort demonstrates the high thrombotic burden of IVCA. We have identified two distinct forms of IVCA, hepatic and extrahepatic, suggesting different underlying mechanisms. Beyond clinical characterisation, we draw attention to this orphan disease and highlight the need for its study and improved care.

FUNDING

Spanish Society of Thrombosis and Haemostasis, Instituto de Salud Carlos III, FEDER, Fundación Séneca.

Bilateral lower limb examinations for deep vein thrombosis: A single-centre pilot study comparing request and report parameters for bilateral and unilateral referrals

INTRODUCTION

Deep vein thrombosis (DVT) is a common pathology with significant morbidity and mortality, often occurring in the lower limb. Ultrasound is the modality of choice for diagnosis of DVT, but all guidance in the United Kingdom assumes a single leg referral. Few studies have addressed the question of bilateral referrals and bilateral DVTs, and it is not known how these should be included in ultrasound protocols. This study aims to compare the request and report parameters of bilateral examinations with those for single leg examinations over a six-month period.

METHODS

A single-centre feasibility study collected data on all single and bilateral leg examinations performed by sonographers, over a six-month period at a small general hospital. Data collected for each examination included the referral and report findings. These were compared using basic statistical methods to compare DVT yield by laterality, referrer, DVT site, and patient factors.

RESULTS

Six hundred and thirty examinations were included, eighteen of which were bilateral examinations. Although the bilateral leg cohort was small, there were significant differences in DVT yield between the groups, with single leg referrals more than eight times more likely to demonstrate a DVT at ultrasound.

CONCLUSION

In a context of limited ultrasound resource, the low DVT yield of bilateral examinations has implications for service design. Further data collection will be needed to validate initial results, and to establish suitable criteria for acceptance of bilateral DVT referrals.

IMPLICATIONS FOR PRACTICE

Low yield of DVTs in bilateral examinations can be validated via further research. Bilateral examinations can be explicitly included in DVT service design.

Inferior Vena Cava Agenesis, a Forgotten Etiology of Deep Vein Thrombosis in Young Patients: A Case Report

Agenesis of the inferior vena cava (IVC) is a rare congenital anomaly that is associated with the development of extensive collateral circulation with the aim of compensating for the inadequate return of blood to the right ventricle. This collateral circulation predisposes to the emergence of venous hypertension with stasis and thrombus formation. Most cases are asymptomatic and are diagnosed incidentally. We report the case of a 28-year-old man who presented with bilateral deep vein thrombosis (DVT) as the first manifestation of agenesis of the IVC. We decided to maintain anticoagulation for an indefinite period of time after a multidisciplinary discussion. IVC agenesis should be considered a cause of DVT in young men, with bilateral and proximal thrombosis and without other risk factors. The rarity of the condition makes its therapeutic approach complex.

Deep venous thrombosis in patients with atresia of the inferior vena cava and right kidney hypoplasia (KILT syndrome): Systematic review of the literature

Inferior vena cava (IVC) anomalies are uncommon congenital causes of deep vein thrombosis (DVT). KILT syndrome (kidney and IVC abnormalities with leg thrombosis) has only been described as case reports in the literature. Therefore, the characteristics, evaluation, and management of patients with KILT syndrome have not yet been standardized. This study aimed to systematically review and analyze the clinical and radiographic data and treatment of previously reported cases of KILT syndrome. In this systematic review, we performed a literature search of the PubMed, Scopus, and Web of Science databases in December 2023, with no restrictions on the publication date. After duplicate extractions, 4195 articles were screened. Case reports and case series reporting on KILT syndrome were included. In addition to previously published cases, we included a new case of a previously healthy 25-year-old man with KILT syndrome in the analysis. A total of 34 cases were therefore included in this study. The majority (76.5%) were male patients with a median age of 24 years. In most patients, unprovoked bilateral iliofemoral thrombosis was diagnosed, and 64.7% had left kidney abnormalities. Our study suggests that anomalies of the IVC should be suspected in all young patients, especially male patients, with proximal, recurrent, or idiopathic DVT. If an IVC anomaly is confirmed, the kidneys should be examined to monitor and preserve healthy kidneys in cases of KILT syndrome. The data collected from all patients emphasize the requirement of long-term anticoagulation and risk factor control. Surgical measures may be effective for treating symptomatic refractory cases.

Endovascular management of KILT syndrome and COVID-19-related extensive deep vein thrombosis in a pregnant patient: A case report

We report on a 20-year-old pregnant woman who tested positive for SARS-CoV-2 and was diagnosed with KILT syndrome, a rare condition that increases the risk of thrombotic events. The patient showed signs of deep vein thrombosis that extended from the bilateral iliac vein to the inferior vena cava (IVC), which was treated with placement of an IVC filter and endovascular thromboaspiration/thrombolysis. The IVC was successfully recanalized; however, during follow-up, thrombotic restenosis occurred at the filter level, requiring filter removal. This case highlights the potential benefits of endovascular thromboaspiration/thrombolysis and IVC filter placement in patients with KILT syndrome presenting with acute thrombotic events.

Azygos vein stenting as an alternate route for inferior vena cava obstruction

Chronic venous insufficiency, caused by inferior vena cava occlusion, can lead to thromboembolic complications and tissue loss. We present two cases of azygos vein stenting (AVS) in which vena cava recanalization techniques were exhausted. In the first case, the left iliac vein and vena cava were recanalized and stented; however, the right iliac vein had been previously resected and required AVS. Conventional recanalization attempts from the right and left iliac systems failed in the second patient with congenital inferior vena cava occlusion; therefore, AVS was chosen to establish in-line drainage.

Systematic review of inferior vena cava atresia

OBJECTIVE

Inferior vena cava (IVC) atresia is a rare venous anomaly characterized by absence of the IVC. It has been associated with deep vein thrombosis (DVT) and other congenital anomalies. The aim of the present study is to provide a comprehensive summary of the literature on IVC atresia and discuss the presentation and outcomes of patients with IVC atresia.

METHODS

A systematic review of the English literature up to April 2020 was performed. The presentations and treatments reported were noted and compared between the two sexes. The IVC atresia cases were further stratified into isolated IVC atresia and IVC atresia associated with other congenital anomalies.

RESULTS

A total of 412 abstracts were screened, with 178 reports included. A total of 376 patients were analyzed. Overall, males seem to be more affected than females, with a ratio of almost 2:1 (male, 227 [64.1%]; vs female, 127 [35.8%]). However, females were more likely to have congenital IVC atresia compared with males (46.1% vs 21.3%; P < .001). The mean age at presentation was 27.9 ± 18.0 years (range, 0-77 years), with no differences between the sexes. Most patients with IVC atresia presented with DVT (n = 242 of 376; 64.3%), with the iliac veins most often affected (n = 159 of 242; 65.7%). No difference was found in the reported proportion of patients presenting with DVT between the two sexes. The symptom presentation was similar, with leg pain and swelling the most common in both sexes. The patients were treated either medically with anticoagulation or surgically (open or endovascular). No mortality was reported with isolated IVC atresia in either treatment group. However, the mortality of patients with IVC atresia associated with other congenital anomalies was 11.7%.

CONCLUSIONS

IVC atresia is more common in males but seems to have a predilection for females in the setting of other congenital anomalies. Most patients present with leg pain and swelling related to the development of DVT. Open and endovascular surgical interventions to treat IVC atresia have been reported in 18.3% of patients reviewed, with acceptable mid-term results in terms of patency and symptomatic relief.

Infrarenal inferior vena cava agenesis presenting as acute abdomen and hydronephrosis - case report

The inferior vena cava agenesis (IVCA) is a rare and often asymptomatic malformation due to the abundant development of the collateral circulation. However, it is frequently found in young people and carries a significant risk of deep venous thrombosis (DVT). It is estimated that about 5% of patients under 30 years of age presenting with DVT have this condition. We report a case of a previously healthy 23-year-old patient presenting with signs of acute abdomen and hydronephrosis due to the thrombophlebitis of an unusual iliocaval venous collateral, which developed secondary to IVCA. After treatment, the iliocaval collateral and hydronephrosis completely regressed on a 1-year follow-up. To our knowledge, this is the first such case reported in the literature.

A rare cause of deep vein thrombosis: inferior vena cava agenesis

Inferior vena cava agenesis is a rare condition and is often misdiagnosed. This anomaly is asymptomatic in the majority of cases and is usually diagnosed during imaging tests carried out for other purposes. The most frequent manifestation is deep vein thrombosis (DVT) in lower limbs and anticoagulation therapy is the most frequent treatment option. Other techniques such as thrombolysis and venous bypass are also described. We report two cases diagnosed at our institution during the last year, both of which presented with an episode of DVT. We opted for indefinite anticoagulation therapy and both patients remain asymptomatic, after 1 year of surveillance in the first case and 6 months in the second, with no new episodes of DVT. Although it is not a life-threatening anomaly, it is important to make an appropriate diagnosis and provide treatment to improve the symptoms and quality of life of these patients.

Venous anomalies and thromboembolism

Patients with venous anomalies are at increased risk of developing venous thromboembolism (VTE) and subsequent complications, but they are often under-recognised. While unprovoked VTE may trigger testing for inherited thrombophilias and malignancy screening, anatomic variants are considered less often. Venous anomalies increase the risk due to venous flow disturbance, resulting in hypertension, reduced flow velocity and turbulence. Recognition is important as endovascular or surgical intervention may be appropriate, these patients have a high rate of VTE recurrence if anticoagulation is ceased, and the anomalies can predispose to extensive VTE and severe post-thrombotic syndrome (PTS). In this case series, we present representative cases and radiological images of May-Thurner syndrome (MTS), inferior vena cava (IVC) variants and venous aneurysms, and review the available literature regarding optimal diagnosis and management in each condition.

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.

A Not So Common Iliac Vein Anomaly: A Case Report

Arising from the external and internal iliac veins, the common iliac veins (CIVs) carry blood from the lower extremities and pelvic region into the inferior vena cava at the level of the fifth lumbar vertebra. It is sometimes common to observe slight anomalies in vascular anatomy in patients; however, anomalies of the CIVs are rare. We present a case of a patient with significant edema of the left lower extremity due to extrinsic compression (May-Thurner syndrome [MTS]) involving a duplicated left CIV found during vascular angiography. Anomalies in pelvic vasculature are well documented in the medical literature; however, documented cases of a duplicated CIV remain few and far between. These anomalies in pelvic vascular anatomy are essential to be aware of to avoid surgical complications and understand their implications in associated pathologies.

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 11^th 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.

Agenesis of the Intrahepatic Inferior Vena Cava: A Case Report and Literature Review

Anomalies of the inferior vena cava (IVC) are an uncommon finding in the general population. A wide range of IVC anomalies has been described in the literature, the majority of which lack clinical significance. Agenesis of the IVC (AIVC) is a rare anomaly of the IVC in the general population. This anomaly may involve either complete agenesis of the IVC or agenesis of a segment of the IVC. Agenesis of the suprarenal segment is the most commonly occurring variant, while agenesis of the infrarenal and hepatic segments is less common. Here we report a case of agenesis of the intrahepatic segment of the IVC.

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.

Inferior Vena Cava Agenesis: An Underrated Cause of Deep Venous Thrombosis

The absence of the inferior vena cava (IVC) is a rare abnormality reported in less than 1% of the population. The condition is usually the result of defects during embryogenesis. The collateral veins are enlarged with agenesis IVC, enabling blood transport to the superior vena cava. Although the alternate pathways enable venous drainage of the lower extremities, IVC agenesis (IVCA) may predispose to venous hypertension and complications, including thromboembolism. This report includes a case of a 35-year-old obese male who presented with deep vein thrombosis (DVT) in his left lower extremity (LLE) with no predisposing factors, which led to an incidental discovery of the inferior vena cava agenesis. Imaging showed thrombosis of the deep veins of the LLE, absence of the IVC, enlarged paralumbar veins, filling of the superior vena cava, and left renal atrophy. The patient responded to therapeutic heparin infusion, and catheter placement and thrombectomy were performed. The patient was discharged on the third day with medications and vascular follow-up. It is essential to recognize the complications of IVCA and its correlation with other findings, such as atrophy of the kidney. The agenesis of IVC is a highly under-recognized cause of DVT of the lower extremities in the young population without other risk factors. Hence, a complete diagnostic evaluation is necessary for this age group, including imaging for vascular anomalies, besides the thrombophilic screening.

Inferior vena cava agenesis: a rare cause of deep vein thrombosis

The development of deep vein thrombosis (DVT) is influenced by a myriad of risk factors which are seen across a wide spectrum of healthcare settings. We present a previously fit and well male in his early 40s with extensive bilateral lower limb DVT associated with total inferior vena cava (IVC) agenesis. The diagnosis was made with contrast-enhanced CT imaging of the abdomen and pelvis. With no demonstrable subhepatic IVC, the majority of the venous drainage was via large azygous veins and distended collateral vessels. Lifelong anticoagulation was advised by both haematology and vascular surgery teams. IVC agenesis represents a very rare and largely unknown clinical entity within the medical community with currently no firmly established pathogenesis, guideline for future VTE prophylaxis or standardised follow-up strategy.

An usual case of bilateral deep venous thrombosis with associated pulmonary embolus

Congenital absence of the inferior vena cava (IVC) triggers collateral vessel growth to drain the peripheries and abdominal organs. This causes venous stasis and increases the risk of deep vein thrombosis (DVT) and pulmonary embolism. Typically, patients with absent IVCs present before 30 years of age, with bilateral DVT symptoms triggered by intense exercise. The abnormality can remain undetected as computed tomography imaging is not usually performed. Due to the increased risk of clotting, these patients should be on life-long anticoagulation. Raising clinical awareness of this condition, to ensure appropriate investigations and treatment, is important.

Iliocaval Reconstruction: Review of Technique, Challenges, and Outcomes

Iliocaval thrombosis is a major source of morbidity for patients, with a range of clinical presentations, including recurrent lower extremity deep venous thrombosis and postthrombotic syndrome. Endovascular reconstruction of chronic iliocaval occlusion has been demonstrated to be a technically feasible procedure that provides long-lasting symptom relief in combination with antithrombotic therapy and close clinical monitoring. Herein, we describe the etiologies of iliocaval thrombosis, patient assessment, patient management prior to and after intervention, procedural techniques, and patient outcomes.

Bilateral proximal deep vein thrombosis and COVID-19 in a patient with absence of inferior vena cava: A case report and review of literature

Bilateral proximal deep vein thrombosis (DVT) in the lower extremities of young patients should raise suspicion over pro-thrombotic conditions and venous anatomical abnormalities, even in the presence of other precipitating factors, such as viral infection. The authors present a 33-year-old man with bilateral DVT and absence of inferior vena cava (AIVC), who also had concurrent COVID-19, and discuss the management of this patient.

Extensive deep venous thrombosis in a young male with absent infrarenal inferior vena cava

A previously well, independent 20-year-old man presented with a 4-day history of progressive left lower limb pain with associated phlegmasia cerulea dolens. Duplex venous ultrasound examination and computed tomography venogram revealed extensive deep vein thrombus from the left popliteal vein to abnormal venous vasculature proximally. Notably, no infrarenal inferior vena cava was detected, with distal venous return channeled through lumbar and visceral collateral channels into the azygous system. Treatment included systemic anticoagulation, catheter-directed thrombolysis, and prolonged therapeutic anticoagulation. In the absence of other risk factors, anatomical abnormalities should be considered in young, well patients presenting with lower limb venous thrombosis.

Rare congenital abnormality resulting in spontaneous bilateral deep venous thrombosis and pulmonary emboli in a young healthy man

This report describes a unique case of a healthy man in his 30s, who presented with progressive unilateral leg swelling with no common risk factors identified. Two days prior to the swelling he had developed significant abdominal pain following a treadmill exercise session. Ultrasound imaging revealed extensive deep vein thrombosis involving bilateral ileo-femoral venous systems, extending up the inferior vena cava (IVC). Further investigation using a CT venogram revealed the rare congenital anomaly of hypoplasia of the renal IVC. Successful treatment involved 48 hours of an intravenous unfractionated heparin infusion, followed by lifelong anticoagulation.

Management strategies and clinical outcomes in patients with inferior vena cava thrombosis: Data from GARFIELD-VTE

BACKGROUND

Inferior vena cava (IVC) thrombosis is a rare form of venous thromboembolism (VTE). The optimal treatment strategies and outcomes are unclear in patients with this presentation.

OBJECTIVE

We aimed to compare baseline characteristics, treatment patterns and 24-month outcomes in IVC thrombosis patients (n = 100) with lower extremity deep vein thrombosis (LEDVT) patients (n = 7629).

METHODS

GARFIELD-VTE is a prospective, observational registry of 10 868 patients with objectively diagnosed VTE from 415 sites in 28 countries.

RESULTS

IVC thrombosis patients were younger (51.9 vs. 59.8 years), more frequently had active cancer (26.0% vs. 8.9%) or history of cancer (21.0% vs. 12.2%), and less frequently had recent trauma or surgery than LEDVT patients. IVC thrombosis was more frequently treated with parenteral anticoagulants alone (35.1% vs. 15.9%), whereas patients with LEDVT more commonly received vitamin K antagonists (32.0% vs. 25.8%) or direct oral anticoagulants (49.0% vs. 35.1%). Thrombolysis (11.0% vs. 3.6%) and surgical/mechanical interventions (4.0% vs. 1.4%) were more frequent in IVC thrombosis. At 24-months, the rate per 100 person-years (95% confidence interval) of all-cause mortality was higher in patients with IVC thrombosis than LEDVT (13.28 [8.57-20.58] vs. 4.91 [4.55-5.3]); the incidence of cancer-associated mortality was comparable as was the incidence of VTE recurrence (4.11 [1.85-9.15] vs. 4.18 [3.84-4.55]). Major bleeding was slightly higher in IVC thrombosis (2.03 [0.66-6.31] vs. 1.66 [1.45-1.89]).

CONCLUSION

In summary, IVC thrombosis patients have higher all-cause mortality rates than those with LEDVT, a finding only partly attributable to malignancy.

Chronic occlusion mimicking agenesis of the inferior vena cava in patients with iliofemoral deep vein thrombosis

Agenesis of the inferior vena cava (IVC) has been described as a risk factor for proximal deep vein thrombosis (DVT). We have described the cases of two patients with iliofemoral DVT who had developed post-thrombotic syndrome (PTS). Both cases were misdiagnosed as IVC agenesis on routine imaging; however, an IVC lumen was successfully identified and recanalized during venography with significant improvement in the patients' PTS symptoms. Patients with iliocaval segment DVT with a misdiagnosis of IVC agenesis might have chronic occlusion imitating agenesis. It is worthwhile to attempt percutaneous recanalization of the IVC lumen in these patients and restoring normal venous flow to prevent the development of PTS.

The inferior vena cava: anatomical variants and acquired pathologies

The inferior vena cava (IVC) is the largest vein in the body, draining blood from the abdomen, pelvis and lower extremities. This pictorial review summarises normal anatomy and embryological development of the IVC. In addition, we highlight a wide range of anatomical variants, acquired pathologies and a common pitfall in imaging of the IVC. This information is essential for clinical decision making and to reduce misdiagnosis.

Congenital Inferior Vena Cava Agenesis with Ulceration and Deep Vein Thrombosis

Objectives

This is one of the few case reports of congenital inferior vena cava atresia (IVCA) with extensive bilateral lower extremity ulcers.

Background

IVCA is a congenital anomaly characterized by poor venous return in the lower extremities with increased risk of deep vein thrombi (DVTs) and, rarely, non-healing ulcers.

Results

A 45-year-old woman with history significant for DVTs presented with extensive bilateral lower extremity ulcers, and a CT scan revealed congenital IVCA. Oedema management, DVT prevention, routine wound care and skin grafts resolved the ulcers.

Conclusion

Congenital venous abnormalities should be included in the differential diagnosis of multiple unprovoked DVTs and non-healing ulcers.

LEARNING POINTS

There are very few reports in the English literature describing inferior vena cava atresia with extensive bilateral lower extremity ulcers.We present our findings as well as new insights into the congenital causes of bilateral lower extremity ulcers and deep vein thrombi (DVTs).Especially for young adults with a history of multiple DVTs and non-healing ulcers, venous abnormalities should be included in the differential diagnosis and advanced imaging should be utilized.

Infrarenal inferior vena cava agenesis and recurrent deep vein thrombosis: a case report and literature review

Inferior vena cava agenesis is a rare congenital vascular defect often diagnosed as an incidental finding in asymptomatic patients. When symptoms arise, it can present with chronic venous stasis or unprovoked deep vein thrombosis (DVT). A 42-year-old man with history of unprovoked right lower extremity (RLE) DVTs was admitted for swelling, pain and erythema to the RLE, concerning for new DVT. Venous Doppler ultrasound showed a chronic DVT of the right proximal femoral vein in addition to an acute DVT of the distal femoral vein. Extensive thrombophilia workup was negative and additional imaging with abdominal computed tomography scan revealed the absence of the infrarenal inferior vena cava. Patient was treated with oral anticoagulation and compression stockings and discharged with clinical improvement. At 3-month follow-up, patient was completely asymptomatic. Recurrent unprovoked DVTs in young patients require exhaustive work up including imaging studies to rule out vascular anomalies.

Inferior Vena Cava Anomalies with Portal Vein System Continuation Presenting as Portal Hypertension with a Long-term Follow-up

Inferior vena cava (IVC) anomalies, such as the absence of an intra-hepatic IVC or IVC hypoplasia, are rare. Usually, these anomalies are asymptomatic and cause few clinical issues. We herien report a 53-year-old woman with IVC anomalies who demonstrated both azygos and portal vein system continuation. Over time, this resulted in gradually progressive portal hypertension due to abnormal hemodynamics. The increased inflow from the IVC to the portal vein system for an extended time may contribute to the development of portal hypertension without liver cirrhosis.

Long-term anticoagulant treatment in patients with inferior vena cava agenesis and deep vein thrombosis

INTRODUCTION

Inferior vena cava agenesis (IVCA) is a rare and underdiagnosed congenital anomaly that predisposes to deep vein thrombosis (DVT). Optimal duration of anticoagulant treatment in these patients is not well established.

METHOD

Observational retrospective study that included all consecutive patients older than 18 diagnosed with IVCA and DVT. Data including demographics, initial clinical presentation, modality of diagnosis, treatment and outcomes were obtained.

RESULTS

In patients with IVCA and DVT (n = 9), mean age was 42 and 66% were males. Five (55,5%) patients had bilateral DVT and the most frequent location was ilio-femoral. Only one patient had concomitant pulmonary embolism (PE). During follow-up (mean of 77.8 months), anticoagulation was withdrawn in 2 patients and both developed recurrence of DVT (22.2%, CI 95% 2.8-60.0). One minor bleeding (11.1%, CI 95% 0.3-48.3), five post-thrombotic syndrome (55.6%, CI 95% 21.2-86.3) and no deaths were registered.

CONCLUSION

In patients with DVT and IVCA, post-thrombotic syndrome was developed in approximately half of the patients. No major bleeding events were recorded during long-term anticoagulant therapy and recurrences occurred only in patients who had anticoagulation withdrawn. These data suggest that extended anticoagulant therapy might be considered in these patients.

A Literature Review and Case Series of DVT Patients with Absent IVC Treated with Thrombolysis

BACKGROUND

Congenital absence of the inferior vena cava is related to deep venous thrombosis (DVT) in 5% of cases with no other risk factors. DVT is normally diagnosed by Duplex, whereas computerized tomography or magnetic resonance imaging is required to visualize this absence, and so, it is often missed but ought to be considered in young patients. There are many existing cases in the literature illustrating this link, but these patients were often managed conservatively with anticoagulation.

CASE SERIES

We report five cases presenting with a DVT who were found to have an absent inferior vena cava after imaging and were treated successfully with thrombolysis and consequently managed with lifelong anticoagulation, between January 2014 and January 2019.

CONCLUSIONS

Anomalies of the inferior vena cava can cause unprovoked DVT. These anomalies are often incidental findings after CT but could change the management plan in these patients. Treatment can be with anticoagulants only, thrombolysis, thrombectomy, balloon angioplasty or stents, and long-term or lifelong anticoagulation to prevent DVT recurrence.

[Pulmonary embolism and inferior vena cava agenesis: An unusual association]

INTRODUCTION

Inferior vena cava agenesis is a rare congenital anomaly, generally associated with thrombophilic conditions, and a predisposing factor for deep venous thrombosis (DVT), rarely complicated by pulmonary embolism, in a young population with atypical clinical features and frequent absence of risk factors.

CASE REPORT

We report the case of a 30-year-old woman who developed a right iliac DVT, initially presenting as a low back pain and complicated by a pulmonary embolism, 8 months after a sleeve gastrectomy. Chest CT angiography revealed abnormalities that led to the diagnosis of inferior vena cava agenesis. Thrombophilic screening showed a heterozygous prothrombin gene mutation G20210A and hyperhomocysteinemia. The patient was treated with rivaroxaban with good results after 2 years of follow-up.

CONCLUSIONS

In young patients without risk factors developing a deep venous thrombosis, an inferior vena cava anomaly should be considered. Although no therapeutic consensus has been currently established, inferior vena cava agenesis seems to be associated with a high prevalence of thrombophilic disorders. Screening could be useful, particularly in patients with a thrombotic family history.

An unusual case of deep venous thrombosis in a young patient: congenital absence of the infrarenal portion of the inferior vena cava

Deep venous thrombosis (DVT) is a commonly encountered diagnosis in clinical practice with a variety of well-established risk factors. Congenital absence of the inferior vena cava (IVC) is an extremely rare but established risk factor for DVT. Patients who develop DVTs are at high risk of long-term complications, including DVT recurrence and post-thrombotic syndrome. Here we report a rare case of a 27-year-old female who presented with an extensive DVT of the right lower extremity secondary to complete absence of the infrarenal portion of the IVC, confirmed on computed tomography. There is little consensus regarding the appropriate management of this patient population, and a brief review of the current evidence follows.

Thrombophlebitis hiding under a KILT - case report on 40 years long-term follow-up of neonatal renal vein thrombosis

Background

Neonatal renal vein thrombosis is a recognised cause of renal and inferior caval vein atresia (IVCA). However, the long-term impact of the condition is underrecognized with a high burden of morbidity for the patient, especially in adulthood. IVCA has been shown to be an independent risk factor for deep venous thrombosis (DVT) with a high risk of recurrence. The acronym KILT for kidney and inferior vena cava anomaly with leg thrombosis summarizes the pathological situation.

Case presentation

We present the case of a 40-year-old patient with pain in the right lower limb resulting from acute thrombophlebitis. No risk factors could be identified. His history was remarkable with two episodes of deep venous thrombosis first of the left, then the right leg 22 years earlier; at that time also, no risk factor was identified. Because of the idiopathic character of that thrombosis, the patient remained on long-term anticoagulation with phenprocoumon. The present thrombophlebitis occurred while the INR was not therapeutic in the preceding weeks. A CT with contrast showed atresia of the inferior vena cava and of the right kidney, and presence of numerous collaterals. A thorough medical history revealed a renal vein thrombosis as a neonate. Anticoagulation was intensified, and stent placement became necessary after a further 2 years.

Discussion and conclusions

KILT syndrome is a rare but underrecognized condition. Complications may arise in young adulthood only, and it is of prime importance to instruct parents of the pediatric patient of the possible consequences of renal vein thrombosis and to assure guidance from the treating physicians throughout adulthood. Diagnosis of IVCA is by CT with contrast or by MRI, and lifelong anticoagulation may be necessary. Since the KILT syndrome is widely underdiagnosed, we challenge the clinicians to keep it in mind when confronted with thrombophlebitis or thrombosis of the young, male and with no other identifiable risk factors for deep vein thrombosis.

Lower extremity endovenous reconstruction for symptomatic occlusive disease in pediatric patients: techniques, clinical outcomes, and long-term stent patencies

BACKGROUND

Endovascular stent reconstruction is the standard of care for chronic venous occlusive disease in adults, but it has not been reported in pediatric patients.

OBJECTIVE

This study reports the technical success, complications, clinical outcomes, and stent patency of iliocaval stent reconstruction for chronic iliocaval thrombosis in pediatric patients.

MATERIALS AND METHODS

Fourteen patients, 13 (93%) male with a mean age of 16.4 years (range: 8-20 years), underwent iliocaval stent reconstruction for chronic iliocaval thrombosis. The mean number of prothrombotic risk factors was 2.5 (range: 0-4), including 7 (50%) patients with inferior vena cava atresia. At initial presentation, the Clinical, Etiology, Anatomy, and Pathophysiology classification (CEAP) score was C3 in 2 (14%) patients, C4 in 11 (79%) patients, and C6 in 1 (7.1%) patient. Time course of presenting symptoms included chronic (>4 weeks) (n=7; 50%) and acute worsening of chronic symptoms (2-4 weeks) (n=7; 50%). Aspects of recanalization and reconstruction, stenting technical success, complications, clinical outcomes and stent patency were recorded. Clinical success was defined as a 1-point decrease in the CEAP. Primary, primary-assisted, and secondary patency were defined by Cardiovascular and Interventional Radiological Society of Europe guidelines.

RESULTS

Most procedures employed three access sites (range: 2-4). Intravascular ultrasound was employed in 11 (79%) procedures. Blunt and sharp recanalization techniques were used in 12 (86%) and 2 (14%) patients, respectively. Stenting technical success was 100%. Two (14%) minor adverse events occurred and mean post-procedure hospitalization was 2.8 days (range: 1-8 days). Clinical success rates at 2 weeks, 6 months and 12 months were 85%, 82%, and 83%, respectively. At a mean final clinical follow-up of 88 months (range: 16-231 months), clinical success was 93%. Estimated 6- and 12-month primary stent patencies were 86% and 64%, respectively. Six- and 12-month primary-assisted and secondary stent patency rates were both 100%.

CONCLUSION

Iliocaval stent reconstruction is an effective treatment for symptomatic chronic iliocaval thrombosis in pediatric patients with high rates of technical success, 6- and 12-month clinical success, and 6- and 12-month primary-assisted and secondary patency rates.

Kidney and inferior vena cava abnormalities with leg thromboses (KILT) syndrome: A case report and literature review

Venous thromboembolism (VTE) is now increasingly recognized within paediatrics. A Canadian VTE registry has estimated the incidence as 0.7 to 1.0 per 100,000 population, with a peak in infancy and adolescence. Congenital inferior vena cava agenesis (IVCA) is an important risk factor that may be unfamiliar to paediatricians. Several case reports have since described an association between IVCA, VTE, and renal hypoplasia, which has been referred to as KILT syndrome (Kidney and IVC abnormalities with Leg Thromboses). We describe the first reported paediatric case of KILT syndrome in Canada. In any young patient presenting with a spontaneous DVT, particularly, if it is bilateral in nature with no co-existing risk factors for thrombus formation, we recommend investigating for the possibility of an underlying congenital vena cava anomaly. The use of prolonged anticoagulant therapy is supported by the inherent life-long risk of recurrent thrombosis associated with IVC anomalies.

[Deep venous thrombosis caused by congenital inferior vena cava agenesis]

Congenital agenesis of the inferior vena cava, although rare, is found preferentially in young patients with proximal deep venous thrombosis. Exact diagnosis can be made thanks to enhanced computed tomography scan and/or magnetic resonance imaging, while Doppler ultrasonography is insufficient to establish an inferior vena cava malformation. A consensus has not yet been established for the treatment but lifelong anticoagulation with elastic stocking support to prevent post-thrombotic syndrome is commonly considered in most cases. We report a case of an unprovoked deep venous thrombosis caused by a congenital agenesis of the inferior vena cava localized to the infrarenal segment, in a 24-year-old man. An anticoagulation with low molecular weight heparin was started and prolonged oral anticoagulation was prescribed. In the absence of the usual thrombotic risk factors, the presence of an inferior vena cava anomaly should be considered.

Rare case of a kidney and inferior vena cava abnormalities with extensive lower extremity deep vein thrombosis in a young healthy male

Kidney and inferior vena cava (IVC) abnormalities with extensive deep vein thrombosis (DVT) is a very rare cause of DVT and has a diverse clinical presentation. Computed tomography (CT) angiography is the gold standard for diagnosis and treatment including thrombectomy, thrombolysis and systemic anticoagulation. We present a rare case of active young healthy male admitted with acute onset of right lower extremity pain and swelling who was found to have extensive DVT on doppler ultrasound. CT abdomen showed extensive clot burden involving right common femoral vein extending into internal and external iliac veins associated with IVC hypoplasia and hypoplastic left kidney. Patient underwent urgent thrombectomy, catheter directed thrombolysis and was discharged home in stable condition on oral anticoagulation.

Inferior Vena Cava Agenesis: An Unusual Cause of Deep Vein Thrombosis and Pulmonary Embolism in Young Adult Patients

Introduction

Inferior vena cava agenesis (IVCA) is one of the many anomalies of this vessel. It is one of the most uncommon anomalies, with an estimated prevalence of 0.0005-1% in the general population. Around 5% of the patients younger than 30 years with a diagnosis of deep vein thrombosis (DVT) have a total or segmental IVCA.

Report

Here two unique cases of young and previously healthy male patients are reported: one with bilateral lower extremity DVT, the second with lower extremity DVT and pulmonary embolism. Both patients were found to have segmental agenesis of the inferior vena cava on computed tomography angiography (CTA). Treatment consisted of ultrasound enhanced thrombolysis (EKOS + alteplase) and venous angioplasty. Both patients were discharged with long-term (up to 24 months) oral anticoagulation and compression stockings. Follow up at 3 and 12 months revealed no new thrombotic episode.

Discussion

IVCA can be asymptomatic but the majority of the symptomatic patients present with DVT. IVCA confers a risk factor for DVT. IVCA should be considered and ruled out as a rare but important risk factor and cause of DVT in previously young healthy patients. Once diagnosed, aggressive treatment must be started because of the high risk of post-thrombotic syndrome.

Anomalous development of the inferior vena cava: Case reports of agenesis and hypoplasia

We reported the cases of two adult male patients who were admitted to our emergency room with abdominal pain and dyspnea caused by gallstones and pulmonary embolism respectively. During the radiological investigations, as collateral findings, we found two anomalous development of the inferior vena cava. These conditions affect about 4% of population and, although asymptomatic or mildly symptomatic, are associated with thrombotic manifestations as deep vein thrombosis and pulmonary embolism. The prompt recognition of these anomalies is necessary in order to prevent the complications associated with these conditions and to set the best therapy for patients.

An Unusual Cause of Cauda Equina Syndrome: Lumbar Epidural Venous Engorgement

BACKGROUND Epidural venous plexus (EVP) engorgement occurs due to many conditions, so it can be easily misdiagnosed. This becomes problematic when the diagnosis requires prompt treatment for a good outcome, especially when it results in cauda equina syndrome (CES). We report a case of extensive iliocaval thrombosis leading to epidural venous plexus and ascending lumbar vein engorgement as an outcome of deep venous thrombosis (DVT) due to probable adverse effects of oral combined contraceptive pills (OCCP). CASE REPORT A 42-year-old woman presented to a rural medical facility with bilateral lower-limb swelling and skin darkening for 2 days. She was transferred to a tertiary medical facility where her condition deteriorated to severe CES. A lower-limbs ultrasonography confirmed the presence of extensive DVT extending to the lower segment of the inferior vena cava. Spine magnetic resonance imaging showed abnormal enhancement of the conus medullaris with thick enhanced cauda equina nerve roots, consistent with a possible case of Guillain-Barré syndrome. However, there was engorgement of the EVP extending to the ascending lumbar, azygos, and hemiazygos veins, which was misdiagnosed. The patient was managed immediately with low-molecular-weight heparin and steroids. She died 4 weeks after admission due to hospital-acquired pneumonia and acute respiratory distress syndrome, probably due to the high dose of steroids. CONCLUSIONS Acute CES has a wide differential diagnosis. This report describes an unusual cause of CES and emphasizes the importance of early recognition to avoid misdiagnosis and management delay. Early identification of this clinical entity markedly decreases morbidity and mortality and thus improves the prognosis. Likewise, underlying causing factors such as venous congestion due to OCCP-related DVT should be considered in the diagnosis.

A Pitfall in the Diagnosis of Bilateral Deep Vein Thrombosis in a Young Man

A 32-year-old man with a history of bronchial asthma was referred for low back pain and bilateral femur pain. Vascular sonography revealed bilateral deep vein thrombosis (DVT) from the femoral veins to the popliteal veins. Computed tomography revealed hypoplasia of the inferior vena cava (IVC) and dilated lumbar veins, ascending lumbar veins, and azygos vein as collaterals. There was no evidence of malignant neoplasm. The results of the thrombophilia tests were within normal limits. Hypoplasia of the IVC is a rare cause of DVT. This anomaly should be considered as a cause of bilateral and proximal DVT, in particular, in young patients without major risk factors.