Endothelial and non-endothelial coronary blood flow reserve and left ventricular dysfunction in systemic hypertension

objectives: we evaluated the impairment of endothelium-dependent and endothelium-independent coronary blood flow reserve after administration of intracoronary acetylcholine and adenosine, and its association with hypertensive cardiac disease. introduction: coronary blood flow reserve reduction has been proposed as a mechanism for the progression of compensated left ventricular hypertrophy to ventricular dysfunction. methods: eighteen hypertensive patients with normal epicardial coronary arteries on angiography were divided into two groups according to left ventricular fractional shortening (fs). group 1 (fs >0.25): n=8, fs=0.29 ± 0.03; group 2 (fs <0.25): n=10, fs= 0.17 ± 0.03. results: baseline coronary blood flow was similar in both groups (group 1: 80.15 ± 26.41 ml/min, group 2: 100.09 ± 21.51 ml/min, p=ns). in response to adenosine, coronary blood flow increased to 265.1 ± 100.2 ml/min in group 1 and to 300.8 ± 113.6 ml/min (p <0.05) in group 2. endothelium-independent coronary blood flow reserve was similar in both groups (group 1: 3.31 ± 0.68 and group 2: 2.97 ± 0.80, p=ns). in response to acetylcholine, coronary blood flow increased to 156.08 ± 36.79 ml/min in group 1 and to 177.8 ± 83.6 ml/min in group 2 (p <0.05). endothelium-dependent coronary blood flow reserve was similar in the two groups (group 1: 2.08 ± 0.74 and group group 2: 1.76 ± 0.61, p=ns). peak acetylcholine/peak adenosine coronary blood flow response (group 1: 0.65 ± 0.27 and group 2: 0.60 ± 0.17) and minimal coronary vascular resistance (group 1: 0.48 ± 0.21 mmhg/ml/min and group 2: 0.34 ± 0.12 mmhg/ml/min) were similar in both groups (p= ns). casual diastolic blood pressure and end-systolic left ventricular stress were independently associated with fs. conclusions: in our hypertensive patients, endothelium-dependent and endothelium-independent coronary blood flow reserve vasodilator administrations had similar effects in patients with either normal or decreased left ventricular systolic func