Enoximone, a post-operative inodilator in patients following mitral valve operation: a prospective and controlled study

Abstract

Inotropic support is often required for post-operative management of patients following mitral valve operation. The use of positive inotropes is limited by tolerance development and increase in myocardial oxygen demand. We have compared i.v. enoximone (E) (group E, n = 13), a recently developed phosphodiesterase (PDE) inhibitor, to the conventional i.v. therapeutics dopamine (D) and glyceroltrinitrate (G) in patients following mitral valve operation. The two groups were comparable in terms of physical and pre-operative haemodynamic data. Haemodynamic measurements including cardiac index (CI) determinations were recorded for the first 18 h post surgery in both groups. Group E received a bolus of 1 mg.kg-1 E followed by 4-20 micrograms.kg-1.min-1 (mean = 5 +/- 2 micrograms.kg-1.min-1) for 14 h according to therapeutic requirements, while group D received dopamine (4-10 micrograms.kg-1.min-1, mean = 3.8 +/- 1.9 micrograms.kg-1.min-1) and glyceroltrinitrate (0.5-5 micrograms.kg-1.min-1; mean = 4 +/- 2 micrograms.kg-1.min-1). Adrenaline was added if the MAP was below 60 mmHg or the CI was below 2.5 in both groups (range 50-500 ng.kg-1.min-1; mean E = 0.7 +/- 2 ng.kg-1.min-1; mean D = 2 +/- 2.8 ng.kg-1.min-1). Bolus injection of E resulted in a rise in CI from 2.6 to 3.21.min-1.m-2 (P less than 0.05) within 30 min, followed by a further rise to a maximum of 3.51.min-1.m-2 6 h post bolus. Termination of the E drip resulted in a drop of CI to baseline values (P less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)