AIM Inferior vena cava aneurysms (IVCA) are rare, unlike aortic aneurysms. The diagnosis and treatment is challenging. This study defines clinical and echocardiographic findings in a prospective cohort of sixteen patients with fusiform IVCA. METHODS AND RESULTS All patients referred to the Mayo Clinic between January 2006 and July 2009 for a clinically indicated echocardiogram (36,128 patients) were screened for a dilated IVC. Sixteen cases of fusiform IVCA were identified. Eleven cases (68.8%) were female. Mean age at presentation was 76 years (range 51-89). Eleven (68.8%) had structural heart disease: with right ventricular (RV) dysfunction in 45.5% (n = 5), moderate or greater tricuspid regurgitation (TR) was seen in 36.4% (n = 4) and RV enlargement was seen in 18.2% (n = 2). The most common clinical indication for echocardiography was dyspnea (25%; n = 4) and heart failure (18.8%; n = 3). The mean IVCA diameter was 4.1 cm (range 3.8-5 cm) and the mean length of the aneurysms was 6.2 cm (range 3.5-8.7 cm), with mean right ventricular systolic pressure of 55 mmHg (range 31-105 mmHg). Five (31.3%) had at least a moderate reduction in right ventricular ejection fraction and five (31.3%) had significant TR. Among these five patients with significant TR, severe TR was present in 80%; (n = 4) and moderate to severe TR was present in 20%; (n = 1). CONCLUSIONS IVC aneurysms are more common in the elderly, and is associated with an increase in right sided heart pressures, significant TR, and RV dysfunction.