[Dose-response relation of intravenous enoximone in congestive cardiac insufficiency]

Enoximone (MDL 17043) is a new generation inotropic drug which acts by inhibiting phosphodiesterase and is endowed with both inotropic and vasodilator properties. The purpose of this study, which involved 23 patients aged from 18 to 75 years in NYHA class III or IV and with evidence of severe haemodynamic disturbances (cardiac index below 2.5 1/mn/m2, pulmonary wedge pressure above 15 mmHg), was to evaluate the acute haemodynamic responses to doses of enoximone that ranged from 0.25 to 2.50 mg/kg administered by bolus intravenous injection. Heart failure was either of ischaemic origin (6 cases) or idiopathic (10 cases) or due to various causes (7 cases). Group A patients (n = 11) received the drug in low doses (less than or equal to 1 mg/kg) as opposed to group B patients (n = 12) who were given high doses (greater than 1 mg/kg). Results were evaluated from the amplitude and duration of the haemodynamic response at maximum effect time (30 min). The following parameters were measured: cardiac index, pulmonary wedge pressure, systemic vascular resistance, mean arterial pressure and heart rate. Cardiac index and pulmonary wedge pressure were significantly improved in both groups (P less than 0.005): cardiac index +39 p. 100 in group A, +55 p. 100 in group B; pulmonary wedge pressure -36 p. 100 in group A, -48 p. 100 in group B; systemic vascular resistance -46 p. 100 in group B. Heart rate and arterial pressure were not significantly altered. The duration of response was 1 to 3 hours in group A patients and 4 to 8 hours in group B patients.(ABSTRACT TRUNCATED AT 250 WORDS)