Rethinking Initial Coronary Evaluation in Type 2 Diabetes: Is CCTA Ready for First-Line Use?

1/3 https://e-kcj.orgDespite substantial advances in cardiovascular prevention and treatment, coronary artery disease (CAD) remains the leading cause of morbidity and mortality in patients with type 2 diabetes mellitus (T2DM).Diabetes accelerates atherosclerosis through endothelial dysfunction, chronic inflammation, and metabolic dysregulation, frequently resulting in diffuse coronary involvement and multivessel disease. 1)In addition, patients with T2DM often present with atypical symptoms or silent ischemia, making clinical recognition of CAD particularly challenging. 2)These features underscore the importance of selecting an appropriate diagnostic strategy for evaluating suspected CAD in this high-risk population.In this issue of the Korean Circulation Journal, Lee et al. 3) report a nationwide cohort study comparing coronary computed tomographic angiography (CCTA) with functional testing as the initial noninvasive diagnostic modality in patients with newly diagnosed T2DM and suspected CAD.Using data from the Korean National Health Insurance Service, the investigators identified more than 93,000 individuals with newly diagnosed diabetes, among whom over 34,000 underwent noninvasive testing.After propensity score matching, 14,895 patients were included in each group.The study demonstrated that CCTA was associated with a significantly lower risk of the composite outcome of acute myocardial infarction (MI) or CAD-related death (adjusted hazard ratio, 0.72; 95% confidence interval, 0.58-0.89;p=0.002).In addition, the rate of invasive coronary angiography (ICA) was lower in the CCTA group (10.6% vs. 16.0%),whereas the yield of revascularization among those undergoing ICA was higher.These findings suggest that an anatomical imaging strategy may facilitate more efficient selection of patients for invasive evaluation.However, given the observational nature of the study and the presence of residual confounding, these associations should not be interpreted as causal.The choice between anatomical and functional testing as the initial diagnostic approach for suspected CAD has long been debated.Functional tests-including treadmill exercise testing, nuclear perfusion imaging, and stress echocardiography-evaluate myocardial ischemia by assessing the physiological consequences of coronary stenosis and have established prognostic value. 4)In contrast, CCTA allows direct visualization of coronary anatomy and plaque burden.In the PROMISE trial, anatomical testing with CCTA did