Left Main Spontaneous Coronary Artery Dissection: Clinical Features, Management, and Outcomes

Background: Spontaneous coronary artery dissection (SCAD) is an uncommon cause of acute myocardial infarction (MI) and is associated with substantial adverse events. SCAD involving the left main coronary artery (LM) is a rare but potentially life-threatening condition. Currently, minimal data on LM SCAD have been reported. Objectives: The aim of this study was to investigate clinical features, contemporary management, and clinical outcomes of patients with LM SCAD. Methods: A systematic review and pooled analysis of published case reports was conducted using “left main” and “dissection” as keywords. The authors screened 1,106 papers in MEDLINE and Embase published between 1990 and 2023. Results: The final analysis included 132 patients (mean age 40 ± 11 years, 80% women) diagnosed with LM SCAD. Remarkably, 36% of cases occurred during pregnancy, and 95% presented with acute coronary syndrome, 22% with cardiogenic shock, and 8% with ventricular arrhythmias. At 120-day median follow-up, all-cause death occurred in 9%, left ventricular assist device implantation or heart transplantation in 4%, recurrent MI in 13%, and urgent myocardial revascularization (MR) in 21%. Compared with conservative management, early revascularization by percutaneous coronary intervention or coronary artery bypass grafting significantly reduced the composite endpoint of all-cause death, left ventricular assist device implantation or heart transplantation, recurrent MI, and urgent MR (adjusted HR: 0.37; 95% CI: 0.20-0.69; P < 0.001). Conclusions: LM SCAD carried significant acute morbidity and mortality. Early revascularization (percutaneous coronary intervention or coronary artery bypass graft) was associated with a lower incidence of early adverse outcomes compared with conservative management, driven largely by reduction in recurrent MI and urgent MR. These hypothesis-generating data should be confirmed in future prospective registries and clinical trials.