Idiopathic obstruction of the inferior vena cava: a review

Rare Congenital Obstruction of the Inferior Vena Cava Diagnosed by Intraoperative Transesophageal Echocardiography

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Idiopathic IVC obstructions are rare and unlikely to be detected by routine testing.

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They can be aberrant membranes, stenoses, or malformed Eustachian valves.

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IVC obstructions may be a cause of congestive hepatopathy.

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IVC obstructions are more likely detected by complete TEE than standard TTE.

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Complete and systematic intraoperative TEE is valuable for cardiac surgery.

Membranous IVC Obstruction Presenting with Antegrade/Retrograde Respiratory Flow in the Intrahepatic Segment in Doppler Imaging and Prostatic and Urethral Congestion

Background

Obstruction of the inferior vena cava (IVC) is infrequent, membranous obstruction of the IVC (MOIVC) being one of its rare causes. Early diagnosis is important, as it can lead to hepatic congestion, cirrhosis and Budd-Chiari syndrome (BCS) and can predispose to development of hepatocellular carcinoma (HCC) in severe cases.

Case Report

We report a case of membranous IVC obstruction at the junction of hepatic and suprahepatic segments in a young male with extensive collateralization and venous aneurysms. Unique findings involved antegrade and retrograde flow during respiration in the upper part of intrahepatic IVC proximal to a large collateral vein as well as prostatic and urethral congestion leading to intermittent urinary hesitancy, which have not yet been described in such cases.

Conclusions

MOIVC is a rare cause of IVC obstruction with typical radiological features. Early diagnosis and management is required due to risk of cirrhosis and HCC. Antegrade and retrograde flow may be seen in incomplete MOIVC above the level of a large collateral vein and it may lead to prostatic and urethral congestion.

Membranous obstruction of the inferior vena cava (obliterative hepatocavopathy, Okuda)

Confusion prevails throughout the world regarding the definition and classification of the Budd-Chiari syndrome. The original patients (Budd and Chiari) described had hepatic vein thrombosis, but this syndrome now encompasses various hepatic venous outflow blocks, of which membranous obstruction of the inferior vena cava (IVC) is the most common. This author has been suggesting that the classical Budd-Chiari syndrome or hepatic vein thrombosis and membranous obstruction of IVC or primary thrombosis of IVC at its hepatic portion are epidemiologically, pathologically and clinically different, and that they should be treated as two clinical entities that are not to be mixed. The two diseases have a different onset, different clinical manifestations and a different natural history. Whereas hepatic vein thrombosis is a severe disease with an acute onset, IVC thrombosis presents mildly at onset, but it recurs and eventually turns into a fibrous occlusion of IVC of varying thickness or stenosis of a various degree. The fibrous IVC occlusion is found as a mysterious thin membrane, but is more often much thicker than a membrane, and therefore 'membrane' is a misnomer. Although the genesis is not established, formation of a thin membrane may be an outcome of recurrent thrombosis. The past congenital vascular malformation theory no longer holds, because the disease occurs mostly in adulthood, and transformation of thrombosis into a membrane has now been well documented pathologically as well as clinically. This author suggests that a term 'obliterative hepatocavopathy' replace membranous obstruction of IVC, the term 'Budd-Chiari syndrome' be abandoned, and that primary hepatic venous outflow block be divided into primary hepatic vein thrombosis and primary IVC thrombosis (obliterative hepatocavopathy).

Aneurysm of the inferior vena cava: case report and review of the literature

Aneurysms of the inferior vena cava (IVC) include a diverse group of anomalies with distinct anatomic and clinical characteristics. We report a diverticular aneurysm of the suprarenal IVC in a 45-year-old man who presented with extensive IVC and unilateral lower extremity thrombosis. A CT scan revealed an 8 cm smooth-walled mass containing thrombus to the right of the IVC and behind the second portion of the duodenum. At laparotomy a connection between the mass and the suprarenal IVC was established. Biopsy of the wall of the mass revealed vascular smooth muscle, thus establishing the diagnosis of a diverticular IVC aneurysm. MR angiography further disclosed interruption of the infrahepatic vena cava and return of renal vein flow via the azygous and hemiazygous veins. Twelve additional cases of IVC aneurysm are reviewed. A proposed classification of these aneurysms into four types consistent with their anatomic and embryologic characteristics is presented.