Unprotected Left Main Coronary Disease and ST-Segment Elevation Myocardial Infarction: A Contemporary Review and Argument for Percutaneous Coronary Intervention

Acute occlusion involving the unprotected left main coronary artery (ULMCA) is a clinically catastrophic event, often leading to abrupt and severe circulatory failure, lethal arrhythmias, and sudden cardiac death. Although coronary artery bypass grafting (CABG) is the standard of care for ULMCA disease in patients with stable ischemic heart disease, uncertainty surrounds the optimal revascularization strategy for patients with ST-elevation myocardial infarction (MI) and ULMCA occlusion who survive to hospitalization, and treatment guidelines in this setting are vague. Percutaneous coronary intervention (PCI) is technically feasible in most patients, has the advantage of providing more rapid reperfusion compared with CABG with acceptable short- and long-term outcomes, and is associated with a lower risk of stroke. PCI of the ULMCA should be considered as a viable alternative to CABG for selected patients with MI, including those with ULMCA occlusion and less than Thrombolysis In Myocardial Infarction flow grade 3, cardiogenic shock, persistent ventricular arrhythmias, and significant comorbidities. The higher risk of target vessel revascularization associated with ULMCA PCI compared with CABG is an acceptable tradeoff given the primary need for rapid reperfusion to enhance survival.