EXCEL (Evaluation of XIENCE versus Coronary Artery Bypass Surgery for Effectiveness of Left Main Revascularization) was an international, open-label, multicenter randomized trial that compared everolimus-eluting stents with coronary-artery bypass grafting (CABG) in patients with left main coronary artery disease. A new Original Article explains how at 3 years, PCI was noninferior to CABG with respect to the rate of death, stroke, or myocardial infarction.
• How are patients with obstructive left main coronary artery disease usually treated?
Left main coronary artery disease is associated with high morbidity and mortality owing to the large amount of myocardium at risk. European and U.S. guidelines recommend that most patients with left main coronary artery disease undergo CABG.
• In what subgroup of patients with left main coronary artery disease might percutaneous coronary intervention (PCI) be an acceptable alternative to CABG?
Randomized trials have suggested that PCI with drug-eluting stents might be an acceptable alternative for selected patients with left main coronary disease. Specifically, in the subgroup of patients with left main coronary disease in the Synergy between PCI with Taxus and Cardiac Surgery (SYNTAX) trial, the rate of a composite of death, stroke, myocardial infarction, or unplanned revascularization at 5 years was similar among patients treated with paclitaxel-eluting stents and those treated with CABG. However, the outcomes of PCI were acceptable only in the patients with coronary artery disease of low or intermediate anatomical complexity, a hypothesis-generating subgroup observation that motivated the EXCEL trial.
Morning Report Questions
Q: Is PCI noninferior to CABG for left main coronary artery disease of low or intermediate anatomical complexity?
A: In the EXCEL trial involving patients with left main coronary artery disease and low or intermediate SYNTAX scores, PCI with everolimus-eluting stents was noninferior to CABG with respect to the primary composite end point of death, stroke, or myocardial infarction at 3 years. The primary composite end-point event of death, stroke, or myocardial infarction at 3 years occurred in 15.4% of the patients in the PCI group and in 14.7% of the patients in the CABG group (difference, 0.7 percentage points; upper 97.5% confidence limit, 4.0 percentage points; P=0.02 for noninferiority; hazard ratio, 1.00; 95% confidence interval [CI], 0.79 to 1.26; P=0.98 for superiority). The relative treatment effect for the primary end point was consistent across prespecified subgroups, including the subgroup defined according to the presence versus absence of diabetes.
Q: What changes in practice since the time of the SYNTAX trial might improve outcomes with PCI?
A: Since the time that the SYNTAX trial was conducted, changes in practice have occurred that would be expected to improve outcomes with PCI. In the EXCEL trial, the authors used everolimus-eluting stents almost exclusively; these stents are associated with a low rate of stent thrombosis. In addition, intravascular ultrasonographic imaging guidance was used in nearly 80% of the patients in the PCI group in the EXCEL trial, a practice that has been associated with higher event-free survival after left main coronary-artery stenting.