AIM: Type 1 diabetes mellitus (T1DM) is associated with an increased risk of ischemic heart disease (IHD). The relative contribution of structural and functional abnormalities of the coronary circulation determining clinically manifested IHD remains unknown. The aim of this study was to assess potential differences in myocardial perfusion at rest and coronary atherosclerosis between asymptomatic T1DM patients and healthy controls.

METHODS: Left ventricular (LV) myocardial perfusion at rest measured as LV myocardial Attenuation Density/LV blood pool Attenuation Density (MyoAD-ratio) and coronary artery atherosclerosis were evaluated with 320-multidetector computed tomography angiography in 57 asymptomatic T1DM patients and 114 sex and age matched controls.

RESULTS: In both groups median age was 53 years (p5,p95: 42,67) and 59.6% were men. Median duration of diabetes in the T1DM group was 35 years (p5,p95: 17,49). Median coronary calcium score was higher in T1DM patients (51 vs. 2, p=0.037) compared with controls. However, a similar frequency of >50% stenosis in one or more coronary arteries was found in T1DM patients and controls (18% vs. 14%, p=0.49). LV myocardial perfusion at rest (MyoAD-ratio) was 18% higher in T1DM patients than controls (0.13 vs. 0.11, p<0.0001). This difference was noted throughout all the LV myocardial segments. In a multiple regression analysis including diabetes, sex, age, cardiovascular risk factors, heart rate, calcium score and coronary stenosis >50%, MyoAD-ratio remained significantly higher in T1DM patients (p=0.0001).

CONCLUSIONS: LV myocardial perfusion at rest is higher in T1DM patients compared with controls independent of coronary atherosclerosis and cardiovascular risk factors.