The efficacy of ibopamine in long-term treatment of dilated cardiomyopathy. A clinical and instrumental evaluation

The aim of this study was to investigate whether long-term treatment with ibopamine (SB-7505), the 3,4-diisobutyryl ester of N-methyldopamine, in patients with severe symptomatic congestive cardiomyopathy is associated with an improvement in cardiovascular conditions. The investigation was carried out in 18 outpatients with idiopathic or post-ischemic dilated cardiomyopathy and chronic severe heart failure (NYHA (New York Heart Association) Class III-IV). Patients were randomly assigned to a protocol in which either digitalis and diuretis (8 patients, Group 2) or the same treatment plus ibopamine (10 patients, Group 1) were given. There were no significant differences between the two groups in age, weight, height, functional class and duration of symptoms. The results obtained showed that cardiovascular conditions worsened dramatically in the group of controls during the 10-week period, irrespective of the treatment with digitalis and diuretics. Some of the parameters deteriorated significantly (p < 0.05 or < 0.01) such as systolic and diastolic left ventricular diameters, fractional shortening, end-systolic stress and pressure/diameter ratio, and other parameters showed a tendency to become worse (exercise time, cardiothoracic ratio). On the contrary, in patients of group 1, ibopamine in association with digitalis and diuretics appeared to preserve left ventricle function from a progressive worsening. None of the parameters deteriorated with ibopamine by contrast with a sharp decrease in the control group. Some of the parameters (fractional shortening, pressure/diameter ratio, exercise time) showed a tendency to improve although not significantly. The data suggest that 10 weeks treatment with ibopamine may prevent any deterioration or even produce a mild improvement in patients with very severe congestive heart failure.