Contemporaneous administration of digitalis and dilazep to subjects with heart failure of ischemic etiology.

The objective of this trial was to determine whether the digitalis-dilazep combination interferes with the inotropic effects of digitalis or produces significant cardiovascular modifications. Twenty patients suffering from heart failure of ischemic or ischemic plus valvular etiologies, undergoing digitalis treatment for at least 3 weeks, were administered dilazep (300 mg/day). Systolic, diastolic blood pressures and heart rate, supine and standing, QS2I, LVETI, PEPI, PEP/LVET, triple product, and percentage diastole were recorded. The controls were undertaken at entry, after the digitalis + dilazep association, and after 1 month of digitalis alone when dilazep was ceased. None of the parameters assessed were modified as a result of dilazep treatment. Since systolic time intervals and the PEP/LVET ratio remained unaltered and equal to the values recorded during digitalis alone, it is concluded that dilazep does not interfere with the inotropic action of digitalis.