An unusual crossed course of separately originating left circumflex and left anterior descending arteries with concomitant anomalies found in multi-slice computed tomography

Coronary artery anomalies occur in approximately in 1–2% of the population. The split origin of branches of the left coronary artery is a relatively common anomaly, usually with no significant observable impairment of cardiac function. The application of multi-slice computed tomography (MSCT) for cardiac imaging is increasing and becoming, along with other techniques, a recognised method of examination of the coronary arteries. In the case presented we observed in an ECG-gated MSCT the anomalous origin and proximal course of the arteries of the left sinus of Valsalva. The ostiae of both coronary arteries were located unusually: the ostium of the LAD was found posterior to the ostium of the LCx. Because of this, the proximal part of the LAD crossed the proximal part of the LCx superiorly. Furthermore, muscular bridges were found in the middle part and in the first diameter branch of the LAD. To our knowledge, this is the first case of a crossed course of the LCx and the LAD to be presented in the literature. Applications of MSCT in coronary imaging are presented in comparison with other diagnostic imaging methods. The advantages and limitations of MSCT as a diagnostic tool for anomalies of the coronary arteries are discussed.