Identification of the pathophysiology of cardiac microvasculopathy in diabetes mellitus and its effect on the remodeling of coronary arteries

Abstract

Background Diabetes mellitus (DM) causes macro- and microvasculopathy. Data on cardiac microvascular changes in large animals are scarce. We sought to determine the effect of DM on macro- and microvascular changes in diabetic pigs and humans. Methods Eight domestic pigs (4 with type I DM and 4 controls) underwent coronary angiography with optical coherent tomography (OCT

at baseline and 1 and 2 months), coronary CT angiography (CCTA), cardiac magnet resonance (CMR) imaging, and histologic examination. Results The diabetic pigs had more irregular capillaries with acellular capillaries and a smaller capillary diameter (11.7±0.33㎛ vs. 13.5±0.53㎛, P<0.001) than those of the control pigs. The OCT showed no significant epicardial stenosis in either group

however diabetic pigs had a greater intima-media thickness. CMR results showed that diabetic pigs had a lower relative upslope at rest (31.3±5.9 vs. 37.9±8.1, P = 0.011) and during stress (18.0±3.0 vs. 21.6±2.8, P = 0.007) than the control pigs, implying decreased myocardial perfusion. Among the 79 patients with ST elevation myocardial infarction, 25 had DM and they had lower myocardial perfusion on CMR as well. Conclusions DM causes increase in intima-media thickness and microvascular remodeling leading to a decrease in myocardial perfusion in large animals at a very early stage of the disease course. Early and effective interventions are necessary to interrupt the progression of vascular complications in diabetic patients.