Effects of lidoflazine on left ventricular function in patients

Objective: The present study evaluated the effects of the nucleoside transport inhibitor, lidoflazine, at a dose of 1 mg/kg, on left ventricular function, Design: Patients were randomly assigned to receive either lidoflazine or saline in a double-blind manner. Setting: A university hospital. Participants: The study was performed in 32 patients scheduled for elective coronary artery bypass surgery. Interventions: Left ventricular pressures were measured with fluid-filled catheters. Data were digitally recorded during pressure elevation induced by tilt-up of the legs. Transgastric short-axis echocardiographic views of the left ventricle were simultaneously recorded on videotape. Systolic function was evaluated with the slope (Ees, mmHg/mL) of the systolic pressure-volume relationship. Diastolic function was evaluated with the chamber stiffness constant (Kc, mmHg/mL) of the diastolic pressure-volume relationship. Cardiac function was assessed at baseline and after administration of either lidoflazine (group A [n = 16]) or placebo (group B [n = 16]). Data were compared using two-factor analysis of variance. Measurements and Main Results: At baseline, diastolic and systolic function were comparable in both groups. Lidoflazine increased Kc from 0.079 +/- 0.015 to 0.125 +/- 0.017 mmHg/mL and decreased Ees from 2.481 +/- 0.213 to 1.217 +/- 0.211 mmHg/mL (p = 0.009 and p = 0.004, respectively). None of these changes occurred when placebo was administered. Conclusions: Administration of lidoflazine before the start of cardiopulmonary bypass impaired left ventricular systolic function but also increased diastolic stiffness. Copyright (C) 1997 by W.B. Saunders Company.