Aortocaval Fistula in Associated with Ruptured Abdominal Aortic Aneurysm Diagnosed by Ultrasonography

Abstract

Aortocaval fistula (ACF) is a rare complication of abdominal aortic aneurysm (AAA). We report a patient with the aid of left femoral vein flow pattern analysis by Doppler sonography. A 73-year old man was transferred from another hospital with history of lower back pain, marked left lower edema, and dyspnea. Therefore, diuretics and catecholamine were given under a provisional diagnosis of primary heart failure. Pulmonary artery flow directed catheter study demonstrated a cardiac output of 11. 5l/min.. We thought that he had a state of high cardiac output failure. The ultrasonography performed for diagnosing a deep vein thrombosis of left femoral vein. A ultrasonography revealed a dilatation of left femoral vein, but thrombus did not present. A pulse Doppler detected arterial blood flow signal during early systolic phase, confirming the suspicion of an arterio venous fistula in abdominal cavity near this location. A computered tomographic (CT) scan revealed a infrarenal AAA. 4.7x5.7 cm in diameter and bilateral common iliac aneurysms. A compressed inferior vena cava rightward by the AAA and a compressed left iliac vein by the left common iliac aneurysm was also confirmed by the CT scan. Digital subtraction angiography revealed an ACF caused by rupture of an AAA. An operation was performed. The fistula was closed and abdominal aorta was replaced with Y-graft. Doppler velocity signal analysis was helpful in confirming the venous disease, too.