Endovascular reconstruction of the inferior vena cava in a patient presenting with deep venous thrombosis with concomitant inferior vena cava hypoplasia and aneurysmal dilatation of the iliac veins

Introduction Congenital malformations of the inferior vena cava are rare and remain an under recognised cause of spontaneous deep venous thrombosis (DVT). The purpose of this case report is to highlight the rare occurrence of a concomitant iliac vein aneurysm and the feasibility of endovascular reconstruction in the presence of extensive iliocaval thrombus burden, especially in cases where other treatment modalities have been unsuccessful. Report This is the report of a 25-year-old male who presented with acute onset left lower limb pain/swelling secondary to extensive iliocaval DVT. This was due to multiple abnormalities of the venous system including hypoplasia of the IVC with aneurysmal dilatation of the iliac veins. He failed an initial management strategy of anticoagulation and thrombolysis but subsequently underwent endovascular reconstruction of the iliocaval system via venoplasty and stenting. Complete symptom resolution and venous patency, including resolution of venous aneurysmal disease, were maintained at twelve-month follow-up. Discussion Reduction of the iliac vein diameter so early after successful reconstruction suggests that the iliac venous aneurysm was secondary to significant venous hypertension, and that if the obstruction causing it is treated, the vein can return to a normal vessel diameter.