Relations of left ventricular mass and systolic function to endothelial function and coronary flow reserve in healthy, new discovered hypertensive subjects

Abstract

Left ventricular hypertrophy (LVH) is prognostically relevant, associated with major cardiovascular risk factors and with atherosclerosis. However, whether LVH is independently associated with impaired coronary flow reserve (CFR) and with endothelial dysfunction is disputed. We assessed the relationship of LV mass and systolic function to CFR and endothelial function in new discovered never treated subjects with essential arterial hypertension, but without coronary artery disease or microalbuminuria. LVH, ejection fraction (EF) and stress-corrected midwall shortening (MWS, a measure of myocardial contractility) were assessed by echocardiography. CFR was assessed by single-photon emission computed tomography and dipyridamole infusion. Endothelial function was evaluated by assessing 1-min postischaemic flow-mediated dilatation of the brachial artery (FMD); nitroglycerine-mediated dilatation (NMD) of the same brachial artery was used as measure of nonendothelium-dependent vasodilatation. In approximately 1 year, we enrolled 21 subjects who met stringent inclusion criteria (47+/-10 years old, 26.6+/-2.8 kg/m2, 78% men). Five patients showed LVH. Multivariate analyses showed a significant negative correlation of LV mass index with FMD (beta=-0.61, P<0.05) but not with NMD, neither with CFR. Stress-corrected MWS showed independent correlation with CFR (beta=0.51, P<0.05). Thus, in clinically healthy, new discovered hypertensive subjects, never treated and mostly in the early stage of arterial hypertension, LVH can be associated with endothelial dysfunction while maximal dipyridamole- dependent CFR may be preserved; nevertheless, a cardiac phenotype presenting with tendency to impaired myocardial contractility, assessed by stress-corrected MWS, showed association with lower CFR in the early stage of arterial hypertension.