Hemodynamic assessment of intravenous bepridil administration in ischemic heart disease

The hemodynamic effects of intravenous administration of bepridil were evaluated in 17 patients with chronic coronary artery disease who underwent cardiac catheterization. Of the 17 patients, 8 received bepridil, 2 mg/kg of body weight, for 15 minutes followed by 1 mg/kg for 15 minutes (group A), and 9 received 3 mg/kg followed by 1 mg/kg (group B). In group A, the systemic blood pressure (BP) decreased (p less than 0.05) and left ventricular end-diastolic pressure increased minimally (p less than 0.05). Heart rate (HR), pulmonary artery pressure, cardiac output (CO), stroke index, pulmonary vascular resistance and systemic vascular resistance (SVR), stroke work index, "contractility" (+dP/dt) and double product (HR X systolic BP) showed no significant change after bepridil infusion. In contrast, in group B, while +dP/dt decreased (p less than 0.01), SVR also showed a strong downward trend and changed significantly more than in group A; in the context of the latter alteration, CO increased significantly. In addition, the double product (less than 0.025) and systemic BP (p less than 0.05) decreased, though other parameters did not vary significantly. Thus, although a modest dose-related negative inotropic effect (decreased +dP/dt) was seen, dose-related direct systemic vasodilatation (decreased SVR) led to improved cardiac performance (increase in cardiac index) at the larger dose.