Coronary to pulmonary artery fistula: morphologic features at multidetector CT

The objective of this study is to evaluate the incidence and morphologic features of coronary-pulmonary artery fistulas (CPAF) by multidetector computed tomography (MDCT). From 2006 to 2008, 5,372 patients underwent ECG-gated cardiac CT scans using 64-slice MDCT at our institute. Among them, 17 cases of CPAF were detected (M:F = 14:3, mean age = 63 years). Chief complaints of patients were chest pain (n = 12), abnormal cardiac test (n = 3), known coronary artery disease (n = 1), and known CPAF (n = 1). We retrospectively analyzed the morphologic features of CPAF, such as origin vessels, draining site, fistula size, and aneurysmal sac. Five cases underwent coronary angiography (CAG) and correlated with MDCT findings. Incidence of CPAF was 0.32% by MDCT. The origin of CPAF was the left coronary artery in five (29.4%), the right coronary artery in two (11.8%) and both coronary arteries in ten cases (58.8%). In regard to the diameter of the detected fistula, the diameter of the largest vessel excluding aneurysm was variable from less than 2 to 5.7 mm. Five patients (29.4%) had a fistula that was shown as one vessel that could be traced, one patient (5.9%) was shown as two vessels, and eleven patients (64.7%) were shown as innumerable multiple vessel networks. Five cases were associated with aneurysm (29.4%). Fistulas were located primarily in the left anterolateral aspect of the pulmonary trunk (82.3%) and mostly the drainage site was the left lateral side of the pulmonary trunk (82.3%). CAG was performed in five cases and revealed identical findings to MDCT. In conclusion, coronary-pulmonary artery fistula is more frequently found than anticipated on MDCT. CPAF is supplied by either single or both coronary arteries and drains to the left side of the pulmonary trunk. It is typically located in the anterolateral aspect of the pulmonary trunk. Sometimes CPAF is associated with aneurysms.