Electrophysiologic predictors of long-term clinical outcome with amiodarone for refractory ventricular tachycardia secondary to coronary artery disease.

Fifty-four patients with a previous myocardial infarction and drug-refractory symptomatic ventricular tachycardia (VT) were treated with amiodarone on a long-term basis (range 6 to 54 months, mean 26) irrespective of the results of programmed ventricular stimulation, which was performed after high-dose oral amiodarone loading for more than 4 weeks. VT was rendered noninducible in 6 of 54 patients (11%) taking oral amiodarone. During a mean follow-up of 32 months, these 6 patients remained free of VT or sudden cardiac death. Forty-eight patients (89%) continued to have VT inducible by programmed ventricular stimulation. However, they could be separated into 2 groups: VT-modified (20 patients) and VT-unchanged (28 patients). In the VT-modified group, the induced VT with amiodarone was slowed or rendered nonsustained, and only 3 of 20 (15%) patients during a mean follow-up of 23 months had well tolerated VT recurrences. In the VT-unchanged group, 16 of 28 patients (57%) had recurrences of VT or ventricular fibrillation during a mean follow-up of 24 months. Sudden cardiac death occurred in 6 of these 16 patients. Thus, programmed ventricular stimulation in patients with VT taking long-term amiodarone may have prognostic implications.