Complete rupture of the anterolateral papillary muscle complicated with acute myocardial infarction due to diagonal branch occlusion.

It is well known that post-infarction papillary muscle rupture of the anterolateral papillary muscle is less frequent than that of the posteromedial papillary muscle. This is thought to be due to a difference in blood supply (single vs dual) of the papillary muscles. Recently, we had two cases in which occlusion of the diagonal branch of the left anterior descending artery was found to be the culprit lesion of acute myocardial infarction leading to complete rupture of the anterolateral papillary muscle. Herein, we report on these two rare successful surgical cases with some review of the literature.