Congenital hypoplasia of the inferior vena cava: an underappreciated cause of deep venous thromboses among young adults.

This report illustrates how newer imaging techniques are identifying vasculopathies as risk factors for deep venous thrombosis (DVT). In this case, a healthy young man presented with a straightforward DVT but without traditional risk factors. Doppler ultrasonography confirmed a proximal clot, and contrast-enhanced computed tomography identified a hypoplastic inferior vena cava (IVC). DVTs cause considerable morbidity and death each year, including approximately 200,000 fatal pulmonary embolisms. Specific treatment of DVTs and long-term management and prevention strategies are contingent on the etiology, which can be determined in approximately 85% of cases. A hypoplastic IVC was discovered during efforts to find the cause of thrombosis, and a Medline search suggests that this anomaly should be considered for young persons with DVTs. DVTs are common and their underlying etiology should be identified to help guide long-term management. Evidence is emerging that an anomalous IVC should be ruled out as a cause of DVT among young patients.