Demonstration of complex coronary-pulmonary artery fistula by MDCT and correlation with coronary angiography.

oronary artery anomalies are rare, with an incidence of 0.2% to 1.2% [1], among which coronary-pulmonary artery fistula is usually detected in 0.1% to 0.2% of coronary angiograms [2–4]. Although not all coronary-pulmonary artery fistulas are clinically or hemodynamically significant, some can result in serious consequences including myocardial ischemia, myocardial infarction, or sudden death [5]. When complex anatomy or intervention is contemplated, coronary angiography may not be sufficient. An ideal investigation technique should be noninvasive and provide a quality anatomic description of the fistula. We report a case of complex coronary-pulmonary artery fistula with two feeding vessels of separate origins: one from the left coronary artery via the left anterior descending artery and another arising from the right coronary sinus. The complex anatomy of the fistula was demonstrated in detail by an MDCT scanner using multiplanar reconstruction and different 3D reconstruction techniques. Case Report A 60-year-old woman was referred to our hospital for management of heart failure. She had a history of hypertension and heart murmur, the latter of which had not been investigated. Chest radiography showed moderate cardiomegaly. ECG showed persistent T wave inversion over V5 and V6 leads but the creatine kinase level was normal. Transthoracic and transesophageal echocardiography were performed and showed findings suspicious for coronary-pulmonary artery fistula. A coronary angiogram was obtained that confirmed coronary fistula draining into pulmonary trunk (Figs. 1A and 1B). Despite various projections, the exact anatomic course of the suspected fistula could not be clearly shown by the coronary angiogram. Contrast-enhanced CT of the heart and great vessels, including coronary arteries, was performed in an attempt to demonstrate the course of the coronary-pulmonary artery fistula. CT coronary angiography was performed using a 16-slice MDCT scanner (Aquilion TSX 101A M16, Toshiba). Imaging parameters of 120 kV, 250 mAs, and 0.5-mm slice collimation were preset for the scan. Given the patient’s heart rate was between 65–70 beats per minute and was electrocardiogram gated (ECG gated), the CT scanner could automatically optimize the scanning parameters for the examination. In this case, gantry rotation speed at 0.4 sec per revolution and a helical pitch of 3.2 were applied. A multisegment reconstruction algorithm was also selected automatically, which effectively improved the temporal resolution to 116 msec from the 200 msec, if a halfreconstruction algorithm was to be used. The examination was performed using a single breath-hold technique to cover 120 mm from the cardiac outflow tract to the apex of heart within a total scanning time of about 30 sec. A total of 120 mL nonionic water-soluble iodinated contrast medium at 370 mg I/mL concentration followed by 30 mL of normal saline IV was administered at a rate of 4 mL/ sec. An automated contrast medium tracing program was applied to trigger the scan when