Evaluation of rerouting surgery of a coronary artery anomaly by magnetic resonance angiography

Abstract

A 25-year-old woman presented with episodes of palpitations, near-collapse, and chest pain. Physical examination revealed no abnormalities. Resting electrocardiogram showed sinus rhythm, normal heart axis without conduction abnormalities, and inverted T waves in leads V1 through V3. Laboratory tests and chest roentgenogram were normal. During exercise testing a nonsustained ventricular tachycardia (230 beats per minute) occurred. Coronary angiography showed an anomalous origin of the right coronary artery (RCA) from the left aortic sinus with a separate ostium. Atherosclerotic changes were not present. The coronary angiogram was inconclusive about the exact course of the RCA and therefore free-breathing, threedimensional coronary magnetic resonance angiography was performed using a 1.5 T MR scanner (Gyroscan ACSNT; Philips Medical Systems, Eindhoven, the Netherlands) [1]. Preoperative coronary magnetic resonance angiography revealed an interarterial course of the RCA between the aorta and pulmonary trunk (Fig 1; Ao aorta, PT pulmonary trunk). This malignant course is associated with an increased risk for myocardial infarction and sudden death, therefore surgical rerouting was planned. At inspection during surgery the ostium of the RCA was located above the commissure between the left and right coronary cusps and proximally coursing within the aortic wall. A small scar was observed in the inferior wall. The slit-like ostium was removed from the aorta and unroofing was performed. Then the ostium was reimplanted in the right coronary sinus. A xenopericard patch was used to close the aortic defect. Aortic regurgitation was excluded by intraoperative transesophageal echocardiography. Postoperative electrophysiological testing could not induce ventricular arrhythmias. After surgery coronary magnetic resonance angiography was repeated and evaluated the success of the rerouting procedure and postoperative course of the RCA (Fig 2; Ao aorta; LV left ventricle; PT pulmonary trunk; RV right ventricle). In our patient, the ventricular tachycardias most likely were caused by paroxysmal ischemia or infarction due to an anomalous RCA. Coronary magnetic resonance angiography can be used to identify the exact course of anomalous coronary arteries and in this case was also applied successfully to evaluate the course of the RCA after surgical rerouting.