Exercise testing of the chronic effects of bunazosin hydrochloride on dilated cardiomyopathy.
Bunazosin hydrochloride (Detantol) was administrated in 3-mg oral doses to 10 patients (6 males and 4 females, average 49.9 years) with dilated cardiomyopathy (DCM) of class II in the NYHA functional classification. The patients were observed for changes in their hemodynamics at rest, chest X-ray, echocardiography, humoral factors and symptom-limited exercise tolerance with treadmill testing before treatment and 4 and 8 weeks after administration. All but the left ventricular end-diastolic diameter after 8 weeks were unchanged. Of the humoral factors, only aldosterone decreased significantly during the treatment. On the other hand, the duration of symptom-limited exercise was prolonged significantly, and for a given exercise load, a reduction of heart rate and systolic blood pressure as well as a drop in the pressure-rate product occurred at 8 weeks after administration. Therefore, bunazosin appears to improve cardiac function and exercise tolerance in the patients with DCM, at dosages which do not affect hemodynamics at rest.
Nakano
A
A
Second Department of Internal Medicine, School of Medicine, Gunma University, Japan.
Tamura
M
M
Hatori
M
M
Hasegawa
A
A
Suzuki
T
T
Murata
K
K
D000293:Adolescent; D000317:Adrenergic alpha-Antagonists / Q000009:adverse effects / Q000627:therapeutic use*; D000328:Adult; D000368:Aged; D002311:Cardiomyopathy, Dilated / Q000188:drug therapy* / Q000503:physiopathology; D004452:Echocardiography; D004562:Electrocardiography; D005080:Exercise Test; D005260:Female; D006439:Hemodynamics / Q000187:drug effects; D006801:Humans; D008297:Male; D008875:Middle Aged; D011799:Quinazolines / Q000009:adverse effects / Q000627:therapeutic use*
D000317:Adrenergic alpha-Antagonists; D011799:Quinazolines; C018176:bunazosin