Prognostic Effect of the SYNTAX Score on 10‐Year Outcomes After Left Main Coronary Artery Revascularization in a Randomized Population: Insights From the Extended PRECOMBAT Trial

BACKGROUND: The long‐term prognostic effect of the SYNTAX (Synergy Between Percutaneous Coronary Intervention With Taxus and Cardiac Surgery) score (SS) after percutaneous coronary intervention (PCI) or coronary artery bypass graft (CABG) for left main coronary artery disease is controversial. METHODS AND RESULTS: In the PRECOMBAT (Premier of Randomized Comparison of Bypass Surgery Versus Angioplasty Using Sirolimus‐Eluting Stent in Patients With Left Main Coronary Artery Disease) trial, 600 patients with left main coronary artery disease were randomized to undergo PCI with drug‐eluting stents (n=300) or CABG (n=300). We compared 10‐year outcomes after PCI and CABG according to SS categories and evaluated the predictive value of SS in each revascularization arm. The primary outcome was a major adverse cardiac or cerebrovascular event (composite of death, myocardial infarction, stroke, or ischemia‐driven target‐vessel revascularization) at 10 years. Among 566 patients with valid SS measurement at baseline, 240 (42.4%) had low SS, 200 (35.3%) had intermediate SS, and 126 (22.3%) had high SS. The 10‐year rates of major adverse cardiac or cerebrovascular events were not significantly different between PCI and CABG in low (21.6% versus 22.2%, P=0.97), intermediate (31.8% versus 22.2%; P=0.13), and high SS (46.2% versus 35.7%; P=0.31) (P‐for‐interaction=0.46). There were no significant interactions between SS categories and revascularization modalities for death (P=0.92); composite of death, myocardial infarction, or stroke (P=0.87); and target‐vessel revascularization (P=0.06). Higher SS categories were associated with higher risks for major adverse cardiac or cerebrovascular events in the PCI arm but not in the CABG arm. CONCLUSIONS: Ten‐year clinical outcomes between PCI and CABG were not significantly different according to the SS. The SS was predictive of major adverse cardiac or cerebrovascular events after PCI but not after CABG. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT03871127.