Abstract
Background: While angina severity is pertinent in determining the management strategy for patients with stable ischemic heart disease (SIHD), its contributing factors and prognostic effect remain unclear, particularly in patients with diabetes mellitus (DM). Methods: From a multicenter percutaneous coronary intervention (PCI) registry, 1,911 consecutive SIHD patients without previous revascularization or heart failure between 2008 and 2015 were analyzed. Angina severity was assessed by the Canadian Cardiovascular Society (CCS) functional classification at the time of PCI. We assessed the contributing factors of CCS III/IV angina. Further, the association between CCS III/IV angina and subsequent occurrence of major adverse cardiac and cerebrovascular events (MACCE: all-cause death, acute coronary syndrome, heart failure, and stroke) within 2 years were analyzed in patients with DM and without DM.Results: A total of 771 SIHD patients (40.3% of all SIHD patients) had DM at the time of revascularization. In the total cohort, 52.4% had CCS I/II, and 13.0% had CCS III/IV angina, with less prevalence of CCS III/IV angina in patients with DM than in those without DM (11.3% vs. 14.2%, P<0.001). In patients with DM, the prevalence of unprotected left main coronary trunk lesions and proximal left anterior descending lesion increased with angina severity. The presence of severe angina at the time of PCI was associated with MACCE in patients with DM (adjusted hazard ratio 1.93; [95% CI 1.01, 3.71]; P=0.047), while no significant difference in those without DM (adjusted hazard ratio 0.82; [95% CI 0.42, 1.59]; P=0.55).Conclusions: In SIHD patients with DM that underwent PCI, severe angina at the time of revascularization was associated with complex coronary anatomies and long-term outcomes. These findings underscore the importance of evaluating angina-related health status while considering revascularization in SIHD patients with DM.