Abstract

Background: Severe left main coronary artery disease (LMD) poses a major treatment challenge in Latin America, where both percutaneous coronary intervention (PCI) and coronary artery bypass grafting (CABG) are used. Methods: This guideline was developed de novo using the GRADE approach. A multidisciplinary panel reviewed evidence from a systematic review of randomized trials comparing PCI and CABG, incorporating a comprehensive literature search of patient values and preferences and outcome utilities. Thresholds were assigned for each clinical outcome, from small to large effect. Results: Five randomized trials enrolling 4612 patients were included. At 30 days, PCI resulted in a large reduction in major bleeding and a small reduction in strokes. At 5 years, PCI was associated with a small to moderate increase of spontaneous myocardial infarction and a moderate to large increase in repeat revascularization. No important differences in short- or long-term mortality were observed between PCI and CABG. The overall certainty of evidence was rated low. There was a notable variability in patient values and a close call on the balance of effects. Conclusions: For patients in Latin America with severe left main coronary artery disease, the guideline panel suggests either PCI or CABG. This is a conditional recommendation, based on low certainty in the evidence (⨁⨁◯◯). It applies when both procedures are clinically and anatomically appropriate and can be performed at centers meeting acceptable standards. The decision should be made through a shared decision-making process involving the patient and the multidisciplinary care team. © 2025 The Authors