Age-Stratified Outcome in Treatment of Left Main Coronary Artery Stenosis: A NOBLE Trial Substudy

Background: In the treatment of left main coronary artery (LMCA) disease, patients' age may affect the clinical outcome after percutaneous coronary intervention (PCI) or coronary artery bypass grafting (CABG). This study stratified the clinical outcome according to the age of patients treated for LMCA stenosis with PCI or CABG in the Nordic-Baltic-British Left Main Revascularization (NOBLE) study. Methods: Patients with LMCA disease were enrolled in 36 centers in northern Europe and randomized 1:1 to treatment by PCI or CABG. Eligible patients had stable angina pectoris, unstable angina pectoris, or non-ST elevation myocardial infarction. The primary endpoint was major adverse cardiac or cerebrovascular events (MACCEs), a composite of all-cause mortality, nonprocedural myocardial infarction, any repeat coronary revascularization, and stroke. Age-stratified analysis was performed for the groups younger and older than 67 years and for patients older than 80 years. Results: For patients ≥67 years, the 5-year MACCEs were 35.7 versus 22.3% (hazard ratio [HR] 1.72 [95% confidence interval [CI] 1.27-2.33], p = 0.0004) for PCI versus CABG. The difference in MACCEs was driven by more myocardial infarctions (10.8 vs. 3.8% HR 3.01 [95% CI 1.52-5.96], p = 0.0009) and more repeat revascularizations (19.5 vs. 10.0% HR 2.01 [95% CI 1.29-3.12], p = 0.002). In patients younger than 67 years, MACCE was 20.5 versus 15.3% (HR 1.38 [95% CI 0.93-2.06], p = 0.11 for PCI versus CABG. All-cause mortality was similar after PCI and CABG in both age-groups. On multivariate analysis, age was a predictor of MACCE, along with PCI, diabetes, and SYNTAX score. Conclusions: As the overall NOBLE results show revascularization of LMCA disease, age of 67 years or older was associated with lower 5-year MACCE after CABG compared to PCI. Clinical outcomes were not significantly different in the subgroup younger than 67 years, although no significant interaction was present between age and treatment. Mortality was similar for all subgroups (ClinicalTrials.gov identifier: NCT01496651).