We report on an octogenarian patient presenting with an acute coronary syndrome due to significant left main coronary artery disease and severe ostial stenosis of the left anterior descending artery disease. Emergent bypass graft performed with "beating heart" consisted of left internal mammary graft to the mid left anterior descending artery with an "over-stent" anastomosis. The immediate post-operative phase was simple, however the patient presented on post-operative day 8 with extensive anterior myocardial infarction and cardiogenic shock. Emergent coronary angiogram showed subocclusive anastomotic stenosis. Percutaneous coronary intervention was performed on left main, proximal left anterior descending, and proximal circumflex arteries. Subsequently, the patient restored a satisfactory hemodynamic condition. A focus on the importance of decision for management of left main disease especially in octogenarian is presented, along with a review of the pertinent literature.