Ranolazine therapy in drug-refractory ventricular arrhythmias

AIMS: Ranolazine is an antiischemic and antianginal agent, but experimental and preclinical data provided evidence of additional antiarrhythmic properties. The aim of this study was to evaluate the safety and efficacy of ranolazine in reducing episodes of ventricular arrhythmias in patients with recurrent antiarrhythmic drug-refractory ventricular arrhythmias or with chronic angina. METHODS: Seventeen implantable cardioverter defibrillator (ICD) recipients, who had experienced a worsening of their ventricular arrhythmia burden, and 12 ICD recipients with angina were enrolled. Patients were followed up for 6 months after the addition of ranolazine (postranolazine). Data were compared with before its administration (preranolazine). RESULTS: In the Arrhythmias group, a significant reduction was found in the median number of ventricular tachycardia episodes per patient (4 vs. 0, P = 0.01), and in ICD interventions in terms of both antitachycardia pacing (2 vs. 0, P = 0.04) and shock delivery (2 vs. 0, P = 0.02) after the addition of ranolazine. Moreover, fewer patients experienced episodes of nonsustained ventricular tachycardia (71 vs. 41%, P = 0.04), ventricular tachycardia (76 vs. 24%, P = 0.01), ICD antitachycardia pacing (47 vs. 18%, P = 0.02), and ICD shocks (47 vs. 6%, P = 0.03). In the Angina group, none of the patients developed major ventricular arrhythmias while on ranolazine treatment. No adverse effects were observed. CONCLUSION: In this small study, ranolazine proved to be effective, well tolerated, and safe in reducing ventricular arrhythmia episodes and ICD interventions in patients with recurrent antiarrhythmic drug-refractory events. In addition, none of the patients with chronic angina developed major ventricular arrhythmias.