RESUMEN
The aim of this study was to evaluate the efficacy and safety of enoximone, an imidazolonic compound inhibiting cardiac phosphodiesterase III, during the postoperative period. The drug was administered prior to the usual stages of weaning the patient off extracorporeal circulation, to a group of 20 subjects who presented an ejection fraction of less than 35% following hemodynamic studies. Patients were randomly subdivided into 4 groups each of which received a different dose of enoximone according to the following protocol: Group A, 1 mg/kg bolus and slow infusion at 10 gamma/kg/min; Group B, 0.5 mg/kg bolus and slow infusion at 15 gamma/kg/min; Group C, 0.5 mg/kg bolus and slow infusion at 10 gamma/kg/min; Group D, slow infusion at 10 gamma/kg/min. The best results in hemodynamic terms and with regard to the positive inotropic and vasodilatory action of the drug in question were obtained in Group C. Increased cardiac output was observed in all patients within 120 minutes of enoximone administration and reduced systemic vascular resistance after approximately 6 hours of infusion. Special attention should be drawn to the use of the drug in patients who do not respond to conventional therapy due to its mechanism of action which is not dependent on beta receptors, thus enabling good results to be achieved even when these are down regulated. Special care must be taken however in administrating enoximone to platelet-deficient patients since the reduction of platelet levels is one of its collateral effect. Other collateral effects observed were: supraventricular arrhythmias and ventricular tachyarrhythmias.