Bepridil therapy: guidelines for patient selection and monitoring of therapy.

Bepridil is a calcium antagonist with a unique electrophysiologic profile, a long elimination half-life, and demonstrated efficacy as an antianginal agent in the setting of chronic stable angina. It is well tolerated, with relatively mild gastrointestinal and neurologic side effects. A major safety concern with bepridil is the occurrence of ventricular arrhythmias, especially torsades de pointes associated with QT interval prolongation, particularly in the context of hypokalemia with concomitant diuretic therapy. An appreciation of the electrophysiologic profile of this compound and the setting in which potentially serious proarrhythmic actions occur allows the identification of patients in whom the drug should be avoided. Among the exclusionary criteria are hypokalemia or risk of hypokalemia, baseline corrected QT interval greater than 0.44 sec, history of serious ventricular arrhythmias requiring treatment with major antiarrhythmic compounds, and concomitant use of other drugs that prolong the QT interval. Appropriate use of this effective antianginal agent requires a knowledge of its electrophysiology and adherence to patient selection and monitoring guidelines.