Effect of ibopamine on the failing heart at rest and during isometric exercise: a noninvasive study.
Eleven patients suffering from heart failure were treated with oral ibopamine, a di-isobutyric ester of N-methyldopamine, 100 mg three times a day for 1 week and 200 mg three times a day for 3 weeks. Therapy was discontinued by one patient because of tachycardia. Left ventricular performance was evaluated with echocardiography and systolic time intervals at rest and after 3 minutes of isometric exercise using a handgrip. Six of 10 patients completing the study were in New York Heart Association (NYHA) functional class III, 2 in class IV, and 2 in class II. All patients, except one who remained stable in class II, improved their subjective condition by one functional class during 4 weeks of therapy (p less than 0.01). There were no changes in heart rate, blood pressure, rate-pressure product, cardiac index, or total peripheral vascular resistance. The left ventricular end-systolic diameter decreased after four weeks from 71.2 +/- 12.7 (SD) to 65.9 +/- 13.0 mm (p less than 0.001); the left ventricular end-diastolic diameter did not change. The ejection fraction increased from 26 +/- 8 to 32 +/- 9% (p less than 0.01). Afterload, that is, left ventricular circumferential systolic wall stress, declined as a result of decreased systolic diameter. Systolic time intervals did not vary. There were no changes due to ibopamine during isometric exercise probably owing to increased beta-adrenergic stimulation induced by the handgrip. Neither urine volume nor body weight changed. Side effects were mild except for tachycardia of one patient.(ABSTRACT TRUNCATED AT 250 WORDS)
Partanen
J
J
First Department of Medicine, University Central Hospital, Helsinki, Finland.
Nieminen
M S
MS
Lehto
H
H
D000328:Adult; D002316:Cardiotonic Agents / Q000494:pharmacology / Q000627:therapeutic use*; D003846:Deoxyepinephrine / Q000031:analogs & derivatives* / Q000494:pharmacology / Q000627:therapeutic use; D004298:Dopamine / Q000031:analogs & derivatives*; D006333:Heart Failure / Q000188:drug therapy*; D006439:Hemodynamics / Q000187:drug effects; D006801:Humans; D007537:Isometric Contraction; D008297:Male; D008875:Middle Aged; D012146:Rest
D002316:Cardiotonic Agents; C023487:ibopamine; D003846:Deoxyepinephrine; D004298:Dopamine