Percutaneous versus surgical revascularization of unprotected left main coronary artery: Data from the Portuguese Registry of Acute Coronary Syndromes (ProACS).

Background: In acute coronary syndromes (ACS), the optimal revascularization strategy for unprotected left main coronary artery (ULMCA) culprit lesion has been under-investigated. Therefore, we compared clinical characteristics and short- and medium-term outcomes of percutaneous and surgical revascularization in ACS.

Methods And Results: Of 31886 patients enrolled in a multicenter, national, prospective registry study between October 2010 and December 2020, 246 (0.8%) had ULMCA as a culprit lesion and underwent percutaneous coronary intervention (PCI) alone (n=133, 54%) or coronary artery bypass grafting (CABG) alone (n=113, 46%). Patients undergoing PCI presented more frequently ongoing chest pain (68% versus 41%, p<0.001) and cardiogenic shock (25% versus 1%, p<0.001). Time from admission to revascularization was higher in surgical group with a median time to CABG of 4.5 days compared to 0 days to PCI (p<0.001). Angiographic success rate was 93.2% in patients who underwent PCI. Primary endpoint (all-cause death, non-fatal reinfarction and/or non-fatal stroke during hospitalization) occurred in 15.9% of patients and was more frequent in the PCI group (p<0.001). After adjustment, surgical revascularization was associated with better in-hospital prognosis (odds ratio (OR) 0.164; 95% confidence interval (CI), 0.04-0.64; p=0.009). Similar results were achieved after propensity score matching. No difference was found at one-year all-cause death.

Conclusion: Percutaneous coronary intervention was the most common revascularization strategy in the ACS with ULMCA culprit lesion. PCI was preferred in unstable patients and presented a high angiographic success. CABG was often delayed and preferred in low-risk patients. At one-year follow-up, PCI and CABG conferred a similar prognosis. The two approaches appear complementary in this high risk cohort.