Disopyramide in hypertrophic cardiomyopathy. II. Noninvasive assessment after oral administration.
The effects of oral disopyramide 150 mg 4 times a day were compared with propranolol 40 mg 4 times a day and placebo in 10 patients with hypertrophic cardiomyopathy and resting obstruction (7 patients) or latent obstruction (3 patients), in a randomized double-blind crossover design; each drug was given for a period of 4 days. As determined from echocardiographic evaluation of systolic anterior motion of the mitral valve, the subaortic pressure gradient was decreased from 61 +/- 20 mm Hg with placebo to 5 +/- 15 mm Hg with disopyramide (p less than 0.01), and 30 +/- 30 mm Hg with propranolol (p less than 0.01). Disopyramide was more effective than propranolol (p less than 0.01). Disopyramide and propranolol both shortened left ventricular ejection time from 352 +/- 51 ms with placebo to 314 +/- 26 and 322 +/- 41 ms, respectively (p less than 0.01). Preejection period was lengthened from 93 +/- 35 ms with placebo to 119 +/- 25 ms with disopyramide, but was unchanged by propranolol at 98 +/- 23 ms. Disopyramide increased exercise duration versus placebo (10.4 +/- 2 vs 9.6 +/- 2 minutes, respectively (p less than 0.05), whereas propranolol produced no significant change (8.8 +/- 2 minutes).
Pollick
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Department of Medicine, Toronto Western Hospital, Ontario, Canada.
D000284:Administration, Oral; D000328:Adult; D000368:Aged; D001794:Blood Pressure / Q000187:drug effects*; D002312:Cardiomyopathy, Hypertrophic / Q000188:drug therapy*; D002986:Clinical Trials as Topic; D004206:Disopyramide / Q000008:administration & dosage / Q000627:therapeutic use*; D004452:Echocardiography; D004562:Electrocardiography; D005080:Exercise Test; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D008991:Monitoring, Physiologic; D011433:Propranolol / Q000008:administration & dosage / Q000627:therapeutic use*; D013599:Systole / Q000187:drug effects; D013997:Time Factors
D011433:Propranolol; D004206:Disopyramide