Superior Mesenteric Vein Aneurysm With Arteriovenous Communication and Portal Vein Thrombosis: A Rare Presentation in Non-cirrhotic Portal Hypertension

Abstract

Visceral venous aneurysms are exceedingly rare clinical entities reported in the literature. Venous aneurysms are usually acquired in origin, with most often portal hypertension as the underlying pathology. Most venous aneurysms are incidental findings on imaging. Complications of venous aneurysms like rupture with catastrophic outcomes had been reported. However, no clear guidelines exist regarding the management of portal venous aneurysms as most of the data is available only from case reports. Here, we report a rare finding of fusiform superior mesenteric vein (SMV) aneurysm with arteriovenous communication and portal vein thrombosis in the background of non-cirrhotic portal hypertension.

Keywords: portal hypertension; superior mesenteric vein aneurysm; venous aneurysm.

Figure 1. Coronal image of CECT showing fusiform proximal SMV aneurysm (yellow arrow) with preserved splenoportal confluence. Thrombosed portal vein with periportal collaterals and gross ascites can also be noted

Figure 2. CECT in the arterial phase showing intense arterial enhancement of the SMV aneurysm. Adjacent SMA with arteriovenous communication is also seen (red arrow)

Figure 3. Intraoperative image showing the fusiform aneurysm of the SMV (black arrow) with superior traction on the pancreas neck region. Tapering of the distal end of the SMV was noted (blue arrow)

Figure 4. Intraoperative image showing the completed interposition mesocaval shunt over the C-loop of the duodenum (black arrow) and the distal most aspect of the SMV aneurysm (blue arrow)