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 mm³ to 668.9 mm³, 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.

Keywords: Alogliptin; Coronary atherosclerosis; Coronary computed tomography angiography (CCTA); Diabetes mellitus; Fractional flow reserve (FFR).

Fig. 1

Study flow chart. FFR, fractional flow reserve.

Fig. 2

Correlation between change in FFR_CT and percentage change in TAV. A significant negative correlation is observed between change in FFR_CT and percentage change in TAV. Δ, change; FFR, fractional flow reserve; TAV, total atheroma volume.