Unprotected left main intervention: the light at the end of the tunnel?

Despite impressive advances in stent technology, unprotected left main coronary artery (LMCA) disease requiring revascularization remains the province of the surgeon at most institutions. In a 2007 editorial, we summarized the evolution of percutaneous coronary intervention (PCI) for LMCA disease, concluding that given the available evidence at that time, coronary artery bypass graft surgery (CABG) should remain the procedure of choice for most good surgical candidates with significant LMCA disease.1 Moreover, just a few months ago in 2009, a consensus document from 6 cardiac societies was published describing “Appropriateness Criteria for Coronary Revascularization,” in which PCI was considered to be “inappropriate” for significant LMCA disease, regardless of the extent of concomitant coronary artery disease, presence or absence of diabetes, and left ventricular function.2 Since these publications, important new evidence has emerged that has challenged the surgical gold standard. In the large-scale multicenter MAIN-COMPARE registry, stent implantation and CABG had comparable 3-year rates of mortality and composite death, Q-wave myocardial infarction, or stroke in patients with LMCA disease, although target vessel revascularization was more common with bare metal stents or drug-eluting stents (DES) than with surgery.3 Of even greater significance, among 1800 patients with LMCA or triple vessel disease randomized to paclitaxel-eluting stents versus surgery in the SYNTAX trial, paclitaxel-eluting stents compared with CABG resulted in nonsignificantly different 1-year rates of death and myocardial infarction, with 76 more revascularization procedures but with 16 fewer strokes per 1000 patients treated, both significant differences.4 The results with paclitaxel-eluting stents were even more favorable in the 705 randomized patient LMCA disease cohort especially among the two thirds of patients with lesser anatomic complexity. Nonetheless, because of the greater revascularization rate with PCI, SYNTAX failed its primary goal of demonstrating noninferiority of paclitaxel-eluting stents compared with CABG for composite major adverse cardiovascular events. Article see p 167