Three-dimensional coronary imaging for the ostium of the left anterior descending artery.

Conventional coronary angiography is subject to a significant foreshortening of the proximal left anterior descending artery and overlapping of the left anterior descending artery and the circumflex artery that limits the accurate identification of the ostium of the left anterior descending artery. The aim of this study was to determine whether the three-dimensional (3D) reconstruction of traditional coronary angiography could optimize the projection angle to clearly show the ostium of the left anterior descending artery. The left main bifurcations of 18 consecutive patients were analyzed. A 3D image of the bifurcation was reconstructed from two conventional images and the optimal projection angle was chosen to clearly identify the ostium of the left anterior descending artery. The optimal angle was the right anterior oblique 18.8 +/- 20.9 degrees-caudal 26.9 +/- 32.3 degrees. The length from the left main trunk to the proximal left anterior descending artery on the optimal views was significantly longer than that on the routine views (25.0 +/- 6.1 vs. 22.4 +/- 5.3 mm, P = 0.011). The angles of the left main bifurcations were not substantially different between the optimal and the routine views. The optimal views selected using the 3D system provided clearer images of the ostium of the left anterior descending artery with less overlapping and foreshortening.