Clonidine and left ventricular function in ten patients with essential hypertension.
Left ventricular mass and function were evaluated by M-mode echocardiography in 10 patients with essential hypertension, before and after 16 weeks of treatment with clonidine. Plasma renin activity (PRA), serum and 24-h urinary Na and K were also determined. The dose range of clonidine was 0.15-0.45 mg/day. Systolic and diastolic blood pressure decreased significantly since the second week of treatment (p less than 0.0001). There was a decrease in calculated total peripheral resistance (35.3 +/- 11.08 to 30.91 +/- 6.6 RU p less than 0.01), end meridional (72.9 +/- 23.6 to 58.5 +/- 22 dynes/cm2 X 10(3), p less than 0.001) and peak systolic wall stress (453.5 +/- 140 to 378 +/- 97 dynes/cm2 X 10(3), p less than 0.01), wall tension (333 +/- 36 to 286.6 +/- 42, p less than 0.01). Left ventricular mass index decreased in six patients (83.7 +/- 20.4 to 70.7 +/- 12.4 g/m2, p less than 0.001). Decrease in left ventricular mass index was related to decrease in wall tension (r = 0.70 p less than 0.01) and septal thickness in diastole (r = 0.71, p less than 0.01). There was a decrease in "double product" (10,934 +/- 1,975 to 8,705 +/- 1,739, p less than 0.01), PRA (3.74 +/- 2.51 to 2.51 +/- 1.44 ng/ml/h p less than 0.01) with increase in 24-h urinary Na (114.9 +/- 37 to 155.3 +/- 55.8 mEq/24-h urine, p less than 0.001). Cardiac index, left ventricular ejection fraction and fractional shortening increased without significance (p = NS).(ABSTRACT TRUNCATED AT 250 WORDS)
D000328:Adult; D000368:Aged; D001794:Blood Pressure / Q000187:drug effects; D003000:Clonidine / Q000627:therapeutic use*; D004562:Electrocardiography; D005260:Female; D006801:Humans; D006973:Hypertension / Q000188:drug therapy* / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D011188:Potassium / Q000652:urine; D012083:Renin / Q000097:blood; D012964:Sodium / Q000652:urine; D013318:Stroke Volume / Q000187:drug effects; D014655:Vascular Resistance / Q000187:drug effects
D012964:Sodium; D012083:Renin; D003000:Clonidine; D011188:Potassium