[Hemodynamic effects of the association of nifedipine and acebutolol].

The aim of this study was to assess the effects of the association of sublingual nifedipine and intravenous acebutolol on left ventricular inotropism. A series of 30 randomised patients underwent hemodynamic investigation repeated after a 30 minute interval comprising measurement of left ventricular (LVP) and aortic (AoP) pressures and ventriculography (Vo). Between the two Vo, Group I (N = 10) were given 20 mg sublingual nifedipine (N), Group II (N = 0) were given I mg/Kg acebutolol (A) intravenously in 5 minutes, and Group III (N = 10) the association of 20 mg sublingual N and I mg/Kg intravenous A. All patients had normal resting left ventricular function (ejection fraction greater than 0,55). In Group I, a significant improvement in left ventricular function with reduction of end diastolic pressure, increase ejection fraction, VCF and cardiac index was observed. THese changes were secondary to the reduction in aortic impedence with no effects on the contractile element (assessed by end systolic pressure/end systolic volume - ESP/ESV - ratio). In Group II, a significant reduction in these indices of left ventricular function was recorded secondary to a reduction in contractility. Group III had a special hemodynamic profile comprising: a reduction in afterload identical to that observed in Group I; a significantly greater reduction in the ESP/ESV ratio than in Group II; a greater reduction in the indices of left ventricular function (especially EF, VCF and CI) than in Group II, but the difference was not significant. The data obtained under the conditions of this acute hemodynamic investigation in patients with normal basal left ventricular function may be summarised thus: 1) Nifedipine alone has no detectable negative inotropic effects. 2) The association with acebutolol, nifedipine seems to potentiate myocardial depression (ESP/ESV). 3) This therapeutic association, the value of which has already been demonstrated in coronary insufficiency should be used carefully without precise knowledge of the left ventricular function.

RCT Entities:   Population Interventions Outcomes