No statistically significant difference in long-term all-cause mortality was observed among Asian patients with unprotected left main coronary artery disease (CAD) who underwent PCI or CABG, based on a non-randomized analysis of the IRIS-MAIN registry presented at TCT 2026 and simultaneously published in The Lancet.

Researchers analyzed data from roughly 7,000 patients from South Korea, India, Japan, Indonesia and Malaysia who were enrolled in the IRIS-MAIN registry, of whom 78% underwent coronary revascularization with PCI using drug-eluting stents (DES) (71%) or isolated CABG (29%). The majority of patients were from South Korea, 78% were male, and the average age was 65 years. The primary outcome was all-cause mortality over a median follow-up of 10 years, calculated using a target trial emulation framework. Propensity-score overlap weighting was used to adjust for measured baseline covariates.

Overall results found no statistically detectable difference in 10-year weighted Kaplan-Meier rates of all-cause mortality between PCI and CABG (24% vs. 23%, respectively). Additionally, exploratory analyses found more spontaneous myocardial infarction and repeat revascularization, as well as numerically fewer stroke events, among patient who underwent PCI compared with CABG. However, “these non-fatal findings warrant cautious interpretation given incomplete and potentially differential ascertainment,” researchers said.

“Because treatment was not randomized and residual confounding remains possible,” Seong-Bong Wee; Duk-Woo Park, MD, PhD, FACC, et al., stress that their findings are observational and complement evidence from other randomized trials, but “do not establish causal treatment effects or equivalence in survival.”

However, they note that for patients considered suitable for either PCI or CABG, a Heart Team discussion may help them weigh potential tradeoffs “alongside their clinical and anatomical characteristics, procedural risks, and preferences.”

Clinical Topics: Cardiac Surgery, Invasive Cardiovascular Angiography and Intervention, Atherosclerotic Disease (CAD/PAD), Aortic Surgery, Interventions and Coronary Artery Disease

Keywords: Transcatheter Cardiovascular Therapeutics, TCT26, Coronary Artery Disease, Drug-Eluting Stents, Percutaneous Coronary Intervention, Myocardial Infarction, Stroke, Coronary Artery Bypass