Biomedical subjects
R Viray
Publications and source records attributed to R Viray.
Hemodynamic effects of flestolol, a titratable short-acting intravenous beta-adrenergic receptor blocker.
The hemodynamic effects of flestolol were evaluated in 30 patients undergoing routine cardiac catheterization. Hemodynamic measurements were obtained during baseline (prior to flestolol), at steady state during IV flestolol infusion (1, 5, and 10 micrograms/kg/min) and at 20 to 30 minutes after discontinuation (postinfusion). Flestolol-induced hemodynamic changes were similar to those induced by other beta blockers without intrinsic sympathomimetic activity. Significant dose-dependent reduction in heart rate, rate pressure product, and increase in peripheral vascular resistance were seen. Flestolol produced clinically insignificant decrease in myocardial contractility as shown by slight decrease in LVdp/dt, CI, and LVEF. Hemodynamic data from patients with paced heart rate, further confirms a direct mild cardiac depressant effect of flestolol, a finding common to other beta blockers. Consistent with the short elimination half-life of flestolol (t1/2 = 6.5 minutes), most of the hemodynamic changes rapidly returned to preinfusion level within 20 to 30 minutes following its discontinuation. Thus flestolol, with its unique pharmacokinetic profile and titrability, may be beneficial in the treatment of critically ill patients.
Esmolol: a short-acting titratable beta-blocker in acute myocardial ischemia.
Esmolol (Brevibloc) is a potent, titratable, cardioselective beta-blocker with a short elimination half-life (t1/2 = 9.2 min) and no intrinsic sympathomimetic activity. It was designed for use in critically ill patients who would benefit from the short duration of beta-adrenergic blockade. Esmolol's short duration of action allows for rapid onset and control of hemodynamic effects. Its safety and efficacy has been demonstrated in patients with acute myocardial ischemia. This review provides a brief summary of the pharmacology of esmolol, as well as experimental and clinical evidence on the use of esmolol in acute myocardial ischemia.