Hybrid CTA/PET imaging of coronary artery disease in non-diabetic, prediabetic and diabetic patients evaluated for chest pain

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Academy of Finland Finnish foundation for cardiovascular research. Background Patients with prediabetes or diabetes are at increased risk of developing cardiovascular disease and cardiac events. First-line coronary computed tomography angiography (CTA) followed by selective use of positron emission tomography (PET) myocardial perfusion imaging is a feasible strategy to diagnose and risk-stratify patients with suspected coronary artery disease (CAD). Purpose To study whether prediabetes or diabetes affects the relationship between imaging-defined CAD and patient outcome. Methods We retrospectively identified consecutive symptomatic patients who underwent coronary CTA for suspected CAD. In patients with suspected obstructive CAD on CTA, myocardial ischemia was routinely evaluated by 15O-water PET myocardial perfusion imaging. The relationship of CAD phenotype and long-term outcome was investigated according to patient’s diabetic status. A composite outcome included all-cause mortality, myocardial infarction (MI), and unstable angina pectoris. Results A total of 1743 patients were included: 1214 (70%) non-diabetic, 259 (15%) prediabetic, and 270 (16%) type 2 diabetic patients. During 6.43 years of follow-up, 164 (9%) adverse events occurred, including 106 deaths, 41 MIs and 17 episodes of unstable angina. The prevalence of normal coronary arteries on CTA was highest in the non-diabetic patients (39%). The prevalence of hemodynamically significant CAD (i.e., obstructive stenosis and abnormal perfusion) increased from 14% in non-diabetic patients to 20% in prediabetic and to 27% in diabetic patients. The lowest event rate was seen in patients with normal coronary arteries (annual event rate 0.2%) and highest in patients with concomitant type 2 diabetes and hemodynamically significant CAD (annual event rate 4.7%). However, neither prediabetes nor diabetes were independent predictors of the composite adverse outcome after adjustment for the clinical risk factors and imaging findings. Conclusions Coronary CTA followed by selective downstream use of PET myocardial perfusion imaging predicts long-term outcome similarly in type 2 diabetic, prediabetic, and non-diabetic patients. Annual event rate % (95% CI)