Purpose: Adiponectin (ADN) is an insulin-sensitizing, anti-atherogenic and anti-inflammatory adipocytokine, with endothelial protective effects. In patients with dilated cardiomyopathy (DCM), absolute myocardial blood flow (MBF) is frequently impaired because of coronary microvascular/endothelial dysfunction. We aimed at evaluating whether the potential effects of ADN on MBF in DCM are modulated by cardiometabolic risk factors. Methods: Sixty-one consecutive patients (46 males, age 59?10 yrs) with LV dysfunction (LV ejection fraction 38?9%, range 19-54%) and angiographically normal coronary arteries were studied. Absolute MBF was measured by positron emission tomography, using 13N-Ammonia as flow tracer, both at rest and during dipyridamole infusion (0.56 mg/kg I.V. over 4 min). Abnormal MBF was defined for resting MBF<0.65 ml/min/g and dipyridamole MBF<1.36 ml/min/g. Plasma adiponectin was measured by a specific ELISA (Linco Research). Cardiometabolic risk factors including age, sex, insulin resistance, lipid profile and obesity were entered into a multivariate linear regression analysis to assess independent determinants of adiponectin and, in turn, their effect on myocardial and microvascular damage. Results: Abnormal MBF was present in 34/61 patients, in 13/31 (42%) with ADN higher than median value and in 21/30 (70%) with ADN levels lower than median value (p<0.05). Among cardiometabolic risk factors, only HDL-cholesterol and obesity were independent determinants of ADN [0.34 (0.13), -0.34 (0.14), β-coefficient (SE), respectively, p<0.05] at multivariate analysis. After correction for HDL-cholesterol and obesity the positive association between ADN and MBF remained significant (p<0.05). Conclusion: ADN is a determinant of MBF in DCM patients and is related with low HDL-cholesterol and obesity
