The study population included 968 patients from the US Department of Veterans Affairs (VA), 386 from the US non-VA, and 931 from Canada with different comorbidities and prognoses. The primary outcome was all-cause mortality or nonfatal myocardial infarction (MI) during the median 4.6-year follow-up. Baseline demographics were similar between percutaneous coronary intervention and optimal medical therapy treatment groups within each HCS