ECE2015 Guided Posters Diabetes and obesity–Clinical obesity and cardiovascular (8 abstracts)
1Division of Endocrinology and Metabolism, Department of Internal Medicine III, Medical University of Vienna, Vienna, Austria; 2Department of Radiology, MR Centre of Excellence, High Field MR, Medical University of Vienna, Vienna, Austria.
Background: Metabolic inflexibility in T2DM might result in reliance on free fatty acids (FFA) as substrates to maintain myocardial energy metabolism compared to lean and healthy controls. Thus, we investigated the effects of an acute suppression of circulating FFA on myocardial lipid content and left ventricular function in extreme phenotypes.
Methods: T2DM patients (age: 56±11a; BMI: 28±3.5 kg/m2; HbA1c: 7.29±0.88%) and nine healthy young controls (age: 24±3a; BMI: 24±3.5 kg/m2) were investigated on two study days in random order. At baseline and at 180 min placebo or Acipimox was administered to inhibit adipose tissue lipolysis. Myocardial lipid content (MYCL) and systolic LV-function was measured by 1H-magnetic-resonance-spectroscopy and tomography at timepoints I (060 min), II (180240 min) and III (420480 min).
Results: In T2DM and controls Acipimox similarly reduced MYCL significantly (T2DM: −0.39±0.07 vs CON: −0.39±0.41% compared to baseline), accompanied by a distinct decrease in parameters of LV systolic function without any difference between both groups (EF −13±8 vs −9±7% compared to baseline; cardiac index: −16±15 vs −11±13% compared with baseline; T2DM vs CON). Baseline MYCL and EF were higher in T2DM compared to controls (MYCL 0.48±0.12% vs 0.18±0.01%; P<0.001; EF: 77±1.7% vs 61±1.2%; P<0.001; T2DM vs CON). At baseline a strong correlation of MYCL and EF (r=0.537; P<0.001) was observed.
Discussion: Pharmacological inhibition of adipose tissue lipolysis reduces MYCL to a similar extent in T2DM and healthy controls. Thus, cardiac lipid stores might be essential for maintaining systolic heart function. These results are of clinical interest, since lipolysis-inhibiting drugs are frequently used in routine care in T2DM (insulin, nicotinic-acids).