[Dual Left Anterior Descending Coronary Artery;Report of a Case].

A 77-year-old male presented with angina pectoris. On coronary angiography, the left anterior descending artery(LAD) was obstructed after branching the second septal branch. Three-dimensional (3D) images constructed with 64-slice computed tomography (CT) showed type I dual LAD. The short LAD, which had been erroneously recognized as a septal branch on coronary angiography, ran on the anterior interventricular sulcus (AIVS) where it then terminated. The long LAD, which was obstructed at its origin, ran on the left ventricular side of the AIVS, and entered the distal part of the AIVS. Coronary artery bypass grafting including a bypass to the long LAD was successfully performed. Recognition of the dual LAD, a rare coronary artery anomaly regarding its origin and course, is import ant in performing successful myocardial revascularization procedures. The 3D-CT images are extremely useful in demonstrating dual LAD, especially in cases where there is occlusion of the LAD.