Abstract |
We investigated the effects of nifedipine on left ventricular diastolic function in 17 asymptomatic or minimally symptomatic patients with hypertrophic cardiomyopathy by simultaneously measuring left ventricular pressure and volume with a catheter-tipped manometer and biplane cineangiography. Studies were performed before and 20 minutes after sublingual administration of nifedipine (20 mg). Heart rates were held constant (79 +/- 12 beats/min, mean +/- SD) by right atrial pacing. Left ventricular volumes and instantaneous rates of left ventricular volume were derived from frame-by-frame (20-msec) analyses of left ventricular biplane angiograms. Left ventricular peak systolic pressure (from 122 +/- 21 to 108 +/- 13 mm Hg, p less than 0.01 vs. control) and mean aortic pressure (from 96 +/- 15 to 87 +/- 11 mm Hg, p less than 0.01) decreased significantly with nifedipine. With afterload reduction, left ventricular ejection fraction (from 0.69 +/- 0.12 to 0.74 +/- 0.08, p less than 0.01) and cardiac output (from 6.4 +/- 2.0 to 7.2 +/- 2.2 l/mm, p less than 0.05) increased significantly. However, there was a slight but significant increase in left ventricular end-diastolic pressure (from 15 +/- 8 to 18 +/- 8 mm Hg, p less than 0.05). Nifedipine did not improve left ventricular relaxation as assessed by the time constants of isovolumic pressure decay (t1/2, from 39.8 +/- 6.6 to 39.4 +/- 7.7 msec, NS; t1/e, from 53.8 +/- 9.0 to 54.4 +/- 10.7 msec, NS).(ABSTRACT TRUNCATED AT 250 WORDS)
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Authors | T Yamakado, H Okano, S Higashiyama, M Hamada, T Nakano, H Takezawa |
Journal | Circulation
(Circulation)
Vol. 81
Issue 2
Pg. 593-601
(Feb 1990)
ISSN: 0009-7322 [Print] United States |
PMID | 2297865
(Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
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Chemical References |
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Topics |
- Cardiac Pacing, Artificial
- Cardiomyopathy, Hypertrophic
(drug therapy, physiopathology)
- Cineangiography
- Female
- Humans
- Male
- Manometry
- Middle Aged
- Myocardial Contraction
(drug effects)
- Nifedipine
(pharmacology)
- Stroke Volume
(drug effects)
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