Despite the progress made in technological advancements, the utilization of stenting for both protected and unprotected left main coronary artery (LMCA) disease remains associated with elevated rates of long-term mortality and significant adverse clinical events, sometimes manifesting as cardiogenic shock. A considerable number of individuals retain the opportunity to receive catheter-based interventional therapy as a viable substitute for re-operative coronary artery bypass grafting (CABG). Despite the changed appearance, patients with acute blockage of the protected LMCA still have major adverse cardiac events (MACE) at a similar rate. Acute occlusion of the unprotected LMCA as an acute coronary syndrome (ACS) is uncommon, but that of the protected LMCA is relatively rare. We present a case of a post-CABG patient who developed ACS as a posterior wall myocardial infarction and acute left ventricular failure due to obstruction of a protected LMCA with substantial stenosis across its distal segment extending to the left circumflex (LCx) artery. The pharmaco-invasive management of the protected LMCA thrombotic occlusion with primary percutaneous coronary intervention resulted in significant patient improvement. These lesions are amenable to complex and high-risk coronary intervention with current technology, and the results have been quite encouraging in terms of long-term survival.