Professional organizations recommend CABG for left main disease. Recently, however, a meta-analysis confirmed that CABG and drug-eluting stents provided similar outcomes in these patients at 1 year (see Reuters Health story of March 24, 2010). Last year, the authors of a smaller long-term study (involving 242 patients followed for up to 11 years), also concluded that stents are a safe and effective alternative to surgery for many such patients (see Reuters Health story of August 19, 2009).
In the May 5th issue of the Journal of the American College of Cardiology, Dr. Seung-Jung Park of the University of Ulsan College of Medicine in Seoul and colleagues report on 2240 patients in the MAIN-COMPARE registry. All received treatment for unprotected left main coronary artery stenosis between 2000 and 2006
Three hundred eighteen patients received bare-metal stents, 784 received drug-eluting stents, and 1,138 underwent CABG. In most cases, the choice of treatment was based on patient or physician preference; only 29 patients had comorbidities that precluded surgery. CABG patients had higher-risk clinical and angiographic profiles.
During a median follow-up of 62 months, 328 patients died, 22 had Q-wave myocardial infarctions (MI), 41 had strokes, and 218 required target vessel revascularization.
After adjustment for baseline covariates, the 5-year mortality rate did not differ significantly between groups (stents vs CABG, hazard ratio 1.13), nor did rates for the composite outcome of death, Q-wave MI or stroke (HR 1.07). Results were similar for bare-metal and drug-eluting stents and for 542 propensity-score matched pairs of patients.
Stented patients were five times more likely to require target vessel revascularization, however (HR 5.11, p < 0.001).
Dr. Park and his associates note that their study was not randomized, and it was underpowered to detect significant differences in serious outcomes. They also lacked detailed information about the burden of atherosclerotic disease and anatomic complexity.
“Because of the narrow margin for error,” they recommend that interventional cardiologists implanting stents in left main lesions “should be experienced and backed by highly competent support from cardiac surgeons.”
In a press statement from the European Society of Cardiology, spokesman Dr. William Wijns said, “This study should be added to the increasing hypothesis-generating signals emerging from various trials and registries that there may be a place for (percutaneous coronary intervention) in the treatment of selected patients with unprotected (left main coronary artery disease)… Ultimately, only a prospective multi-center randomized trial will provide the definitive answer.”
Dr. Wijns, from the Aalst Cardiovascular Centre in Belgium, was not involved in the research.
J Am Coll Cardiol 2010.