Bepridil for recurrent sustained ventricular tachycardias: assessment using electrophysiologic testing.

Bepridil was found to possess electrophysiologic properties common to class I and IV antiarrhythmic agents. Intravenous and oral bepridil were evaluated using serial electrophysiologic studies in a selected group of 9 patients with recurrent sustained ventricular tachycardia (VT) unresponsive to usual therapy, including amiodarone therapy in 15 patients. Intravenous bepridil treatment terminated sustained, well tolerated, pacing-induced VT in 3 of 6 patients and prevented the initiation of VT in 2 of these and in a patient in whom the drug failed to restore sinus rhythm. Oral bepridil was administered at a loading dose of 800 mg on day 1, and 500 to 600 mg the following days, and programmed electrical stimulation was repeated 2 to 6 days after initial study. Oral bepridil therapy prevented VT initiation in 6 patients (66%). The tachycardia cycle length was prolonged (30 to 105 ms) in 2 patients in whom VT remained inducible. In 1 patient the tachycardia cycle length significantly shortened after bepridil and prompt cardioversion was required. Five of the 6 patients with successful results underwent long-term oral treatment with bepridil. VT recurred in 1 patient during the hospitalization period and an adverse effect (paralytic ileus) in another patient required drug discontinuation. Three patients remain symptom-free over a follow-up of 4 to 13 months. These data suggest that bepridil may be useful in patients with recurrent, sustained VT.