Anomalous origin of the left circumflex coronary artery from the first diagonal branch presented as acute myocardial infarction.

Coronary artery anomalies are diagnosed in 0.6 to 1.5% of patients who undergo coronary angiography (CAG). They may present with life threatening conditions but are generally asymptomatic. Recognition and adequate visualization of the anomaly is essential for correct management of the condition. However, in some cases the exact orifice and course of an anomalous coronary vessel cannot be selectively identified by CAG. In this report, a 54-year-old man was admitted to the hospital with acute inferior myocardial infarction and had an anomalous origin of the left circumflex coronary artery (LCX) from the first diagonal branch (D1). In CAG, the right CAG showed no significant stenosis and fortunately we found an anomalous origin of the LCX from the D1. The course of LCX was precisely established by 64-slice multi-detector computed tomography.