Abstract 710: Pioglitazone Treatment Reduces Epicardial Fat in Patients with Type 2 Diabetes Mellitus and Improves Left Ventricular Diastolic Function
Visceral obesity is recognized as a risk factor for cardiovascular events and for diastolic dysfunction. Epicardial fat pad (EFP) is visceral adipose tissue, contains pro-inflammatory substances, and directly attached to epicardial coronary artery. It sometimes infiltrates into cardiac muscle, that may impair diastolic performance. Pioglitazone can reduce the abdominal visceral fat, that is associated with improvement of insulin sensitivity. In this study, we investigated whether pioglitazone can reduce EFP and can improve diastolic function in patients with type 2 diabetes mellitus (DM). Study population consisted of 97 DM patients. All patients underwent echocardiographic examination before and a mean of 9.1 months after pioglitazone. We measured end-systolic thickness of echo free space in front of the free wall of right ventricle to measure EFP. To assess LV diastolic performance, we measured early peak mitral annulus velocity (e′, cm/s) with tissue Doppler. HbA1c decreased (8.1 vs. 7.0%, p=0.0009), trigliceride decreased (179 vs. 135 mg/dl, p=0.0009), and HDL-cholesterol increased (49 vs. 52 mg/dl, p=0.003). Although there was no difference in body weight, EFP thickness significantly decreased (6.3 vs. 5.0mm, p<0.0001) after pioglitazone. Patients were divided into two groups based on EFP thickness at baseline (median value = 6 mm). The percent reduction in EFP is greater in thicker EFP group (≥ 6.0 mm)than in thinner EFP group (<6.0mm) (24 vs. 12 %). Although e′ velocity was comparable before and after pioglitazone in the thinner EFP group, it significantly increased in the thicker EFP group (5.7 vs. 6.7 cm/s, p=0.003). Pioglitazone treatment reduces EFP associated with an improvement in glucose control and in lipid profile among patients with DM. In patients with thicker EFP, the reduction of EFP was greater, that is associated with the better improvement in LV diastolic performance.