Changes in coronary atherosclerosis, composition, and fractional flow reserve evaluated by coronary computed tomography angiography in patients with type 2 diabetes

Abstract Background The use of coronary computed tomography angiography (CCTA) for noninvasive anatomic detection of coronary artery disease is increasing. Recently, fractional flow reserve (FFR) assessment using routinely acquired CCTA datasets (FFR CT ) has been developed. However, there are no reports about changes in coronary atherosclerosis, composition, and FFR CT in patients with type 2 diabetes. Methods This prospective, multicenter, observational trial evaluated changes in coronary atherosclerosis after alogliptin therapy in patients with type 2 diabetes. Fifty-one patients with type 2 diabetes who underwent CCTA examination and having intermediate coronary artery stenosis were treated with 25 mg of alogliptin. After 48 weeks, CCTA examination was repeated. The primary endpoint was changes in FFR CT , and the secondary endpoint was changes in total atheroma volume (TAV) from the baseline to the 48-week follow-up. Results The FFR CT decreased from the baseline to follow-up, but not significantly. A significant increase in TAV (from 658.5 mm 3 to 668.9 mm 3 , p  = 0.048) was observed. Vessel volume tended to increase, whereas percentage atheroma volume and lumen volume did not change. A significant negative correlation was observed between percentage change in TAV and change in FFR CT ( r  = −0.185, p  = 0.048). A significant increase in calcified plaques ( p  = 0.01) and a decrease in intermediate-attenuation plaques ( p  = 0.006) was observed. Conclusions In Japanese patients with diabetes and intermediate coronary artery stenosis, alogliptin could not improve FFR CT or reduce atheroma volume, whereas the plaque composition changed. A progression of atheroma volume was associated with a reduction in FFR CT .