Modification of blood pressure and systolic time intervals by diuretics and beta-blockers in essential hypertension.
Heart rate (HR), blood pressure and systolic time intervals (STI), including total electromechanical systole (QS2), left ventricular ejection time (LVETc), pre-ejection period (PEPc), the PEP/LVET index and the time to the peak of carotid upstroke (Ut), were measured in 24 patients with moderate essential hypertension after 15 days of treatment with oral furosemide (F), hydrochlorothiazide (H), propranolol (P), atenolol (A), furosemide + propranolol (F + P) and hydrochlorothiazide + propranolol (H + P). Except F, all treatments significantly reduced blood pressure; maximal reductions were brought about by A and H + P. The heart rate was most reduced by A. THe QS2c interval was reduced only after F and H, LVETc was significantly reduced by H, A and H + P. Drug combinations prolonged PEPc, while the PEP/LVET index was increased only by H + P. Beta-blockers significantly prolonged the Ut. It is concluded that diuretics shorten QS2c mainly through reduction in blood volume. The H + P combination diminishes contractility and cardiac output and should not be employed in heart failure.
D000319:Adrenergic beta-Antagonists / Q000627:therapeutic use*; D000328:Adult; D001262:Atenolol / Q000627:therapeutic use; D001794:Blood Pressure / Q000187:drug effects; D004232:Diuretics / Q000627:therapeutic use*; D005260:Female; D005665:Furosemide / Q000627:therapeutic use; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D006852:Hydrochlorothiazide / Q000627:therapeutic use; D006973:Hypertension / Q000188:drug therapy*; D008297:Male; D008875:Middle Aged; D011433:Propranolol / Q000627:therapeutic use; D013599:Systole / Q000187:drug effects
D000319:Adrenergic beta-Antagonists; D004232:Diuretics; D006852:Hydrochlorothiazide; D001262:Atenolol; D005665:Furosemide; D011433:Propranolol