title: Decreased left ventricular contractility reserve in patients with never-treated essential hypertension.
abstract: 1. Left ventricular diastolic dysfunction is often present in patients with essential hypertension. To determine whether left ventricular systolic function is normal or subnormal, we evaluated the global left ventricular contractile reserve in patients with untreated essential hypertension. 2. Thirty-one untreated men with essential hypertension and 12 normotensive healthy men were evaluated. Hypertensives were divided into two groups based on the presence (group Hc; n = 21) or absence (group Hn; n = 10) of concentric left ventricular geometric remodelling, which was defined as a relative wall thickness > or = 0.45 on M-mode echocardiography. We compared echocardiographic data of left ventricular function in hypertensive men with those in healthy men under beta-adrenoreceptor activation by up to 10 microg/kg per min dobutamine infusion. 3. At baseline, endocardial (eFS) and midwall fractional shortening of the left ventricle, the early peak filling velocity (E), the peak late filling velocity (A) and the ratio E/A were similar in the three groups. During dobutamine infusion, eFS was significantly lower in groups Hc and Hn (54.1+/-9.2 and 54.1+/-7.9%, respectively) than that observed in group N (61.7+/-7.4%). In addition, eFS was highly correlated with circumferential end-systolic wall stress (ESS) during dobutamine infusion in the three groups. In 11 subjects in group Hc (52%), the eFS-ESS relationship was lower than the 95% confidence limit of the normal regression. Comparing group Hc with groups N and Hn, it was found that E (0.52+/-0.12, 0.71+/-0.16 and 0.63+/-0.15 m/s, respectively) and E/A (0.74+/-0.23, 1.24+/-0.53 and 0.98+/-0.37, respectively) were significantly lower. 4. Our results suggest that, in addition to diastolic dysfunction, the reserve of systolic function decreased under beta-adrenoceptor activation in patients with essential hypertension.
authors.affiliation: Department of Internal Medicine, Sanraku Hospital, Tokyo, Japan. tane.med3@med.tmd.ac.jp
authors.forename: M
authors.initials: M
authors.lastname: Tanaka
authors.forename: Y
authors.initials: Y
authors.lastname: Hashimoto
authors.forename: F
authors.initials: F
authors.lastname: Numano
mesh_terms: D000318:Adrenergic beta-Agonists / Q000008:administration & dosage; D000328:Adult; D000465:Algorithms; D004280:Dobutamine / Q000008:administration & dosage; D004562:Electrocardiography / Q000187:drug effects; D006801:Humans; D006973:Hypertension / Q000503:physiopathology*; D007262:Infusions, Intravenous; D008297:Male; D008875:Middle Aged; D009200:Myocardial Contraction / Q000187:drug effects / Q000502:physiology*; D016277:Ventricular Function, Left / Q000187:drug effects / Q000502:physiology*
chemical_list: D000318:Adrenergic beta-Agonists; D004280:Dobutamine