Cardiovascular effect of oral calcium supplementation: echocardiographic study in patients with essential hypertension.
Oral calcium (Ca) supplementation mildly reduces blood pressure. The authors studied the effects of Ca supplementation on the cardiovascular system in patients with mild to moderate essential hypertension. Twelve patients aged forty-nine to seventy years (7 men and 5 women, mean age with 60.3 +/- 7.2 years) participated. The investigators orally administered Ca (1.0 g/day for one week) under hospitalization, adding to a dietary intake of Ca (0.6 g/day). Left ventricular function and systemic arterial compliance were evaluated by M-mode and pulsed Doppler echocardiographies before and after seven days of Ca supplementation. Left ventricular contractility and afterload were not changed. Preload indicated by end-diastolic volume was significantly decreased after Ca supplementation (109.6 +/- 8.5 vs 107.3 +/- 8.2 mL, P < 0.05). Myocardial relaxation evaluated by IIa-mitral valve opening time (87.7 +/- 6.7 vs 82.1 +/- 6.2 ms, P < 0.01) and maximum descending rate of the left ventricular posterior wall (10.6 +/- 1.0 vs 12.4 +/- 1.0 cm/s, P < 0.01), and atrioventricular net compliance assessed by the descending slope of rapid filling flow in the left ventricular inflow tract (2.63 +/- 0.24 vs 2.26 +/- 0.17 m/s2, P <0.05), as well as systemic arterial compliance (2.05 +/- 0.20 vs 2.73 +/- 0.26 mL/mmHg, P < 0.01) were significantly improved by Ca supplementation. Oral Ca supplementation improved the disturbed left ventricular diastolic function and systemic arterial compliance.
Dazai
Y
Y
The Second Department of Internal Medicine, Ehime University School of Medicine, Ehime, Japan.
Kohara
K
K
Iwata
T
T
Sumimoto
T
T
Hiwada
K
K
D000284:Administration, Oral; D000368:Aged; D001794:Blood Pressure / Q000187:drug effects; D001808:Blood Vessels / Q000187:drug effects*; D002136:Calcium, Dietary / Q000627:therapeutic use*; D002302:Cardiac Output / Q000187:drug effects; D002306:Cardiac Volume / Q000187:drug effects; D004452:Echocardiography; D018619:Echocardiography, Doppler, Pulsed; D005260:Female; D006321:Heart / Q000187:drug effects*; D006760:Hospitalization; D006801:Humans; D006973:Hypertension / Q000000981:diagnostic imaging* / Q000178:diet therapy*; D008297:Male; D008875:Middle Aged; D008943:Mitral Valve / Q000187:drug effects; D009200:Myocardial Contraction / Q000187:drug effects; D017534:Radial Artery / Q000187:drug effects; D013318:Stroke Volume / Q000187:drug effects; D018924:Vascular Capacitance / Q000187:drug effects; D016277:Ventricular Function, Left / Q000187:drug effects
D002136:Calcium, Dietary