Prognosis after revascularization for left main coronary artery disease: insights from the crystal ball

This editorial refers to ‘Long-term forecasting and comparison of mortality in the Evaluation of the Xience Everolimus Eluting Stent vs. Coronary Artery Bypass Surgery for Effectiveness of Left Main Revascularization (EXCEL) trial: prospective validation of the SYNTAX Score II’†, by C.M. Campos et al. on page 1231. Obstructive left main coronary artery (LMCA) disease is encountered in >5% of patients undergoing coronary angiography.1 Because of the large area of downstream myocardium supplied by the left main stem—more than 80% of the left ventricle in right dominant systems, 100% in left dominant systems2—successful revascularization of LMCA stenosis is usually associated with considerable improvement in both symptoms and survival in comparison with medical treatment alone.3 Against this, the consequences of revascularization failure are greater and, accordingly, much debate has centred on the preferred revascularization modality—coronary stenting or bypass surgery—for patients with LMCA disease. A number of previous randomized trials enrolling patients with LMCA disease have shown comparable mortality between patients treated by either drug-eluting stenting or bypass surgery over the short to medium term (see Figure 1).4–6 The largest of these was a pre-specified subgroup of the Synergy between PCI with Taxus and Cardiac Surgery (SYNTAX) trial (enrolling 705 patients).6 This study showed not only similar rates of death with both treatments but also comparable rates of overall major adverse cardiac events at 12 months, suggesting genuine clinical equipoise between the two approaches. Moreover, recent publication of 5-year results from this study confirmed the overall comparability of outcomes with both strategies over the longer term.7 Accordingly, the choice of revascularization strategy is probably best made in a shared decision-making approach taking into account both individual patient characteristics and preferences as well as local considerations relating to the availability and expertise of cardiac surgery and interventional cardiology. Indeed current European guidelines on myocardial revascularization support this approach, recommending that patients with LMCA disease can be treated with either coronary stenting (class I or IIa recommendation) or bypass surgery (class I recommendation) unless there is concomitant anatomical highly complex disease, in which circumstance bypass surgery should be preferred.8