September 3, 2011
View Full PaperRanolazine Reduces Ventricular Tachycardia Burden and ICD Shocks in Patients with Drug‐Refractory ICD Shocks
Key Result
Ranolazine treatment resulted in a significant reduction in ventricular tachycardia and no ICD shocks in 92% of patients with antiarrhythmic-drug-refractory VT over a 6-month follow-up.
Study Design
Type
Observational (n=12)
Structured PICO
Does ranolazine reduce VT burden and ICD shocks in patients with AAD-refractory VT?
P
Population
12 patients with antiarrhythmic-drug (AAD)-refractory ventricular tachycardia (VT) with recurrent implantable cardioverter defibrillator (ICD) shocks. Mean age 65 ± 9.7 years, 92% male, 83% ischemic heart disease, average ejection fraction 0.34 ± 0.13. All patients were on a class III AAD.
I
Intervention
Ranolazine added to background antiarrhythmic therapy
O
Outcome
Reduction in VT burden and ICD shockshard clinical
Ranolazine effectively reduced VT burden and eliminated ICD shocks in a small cohort of patients with AAD-refractory VT.
Abstract
BACKGROUND: There are limited options for patients who present with antiarrhythmic-drug (AAD)-refractory ventricular tachycardia (VT) with recurrent implantable cardioverter defibrillator (ICD) shocks. Ranolazine is a drug that exerts antianginal and antiischemic effects and also acts as an antiarrhythmic in isolation and in combination with other class III medications. Ranolazine may be an option for recurrent AAD-refractory ICD shocks secondary to VT, but its efficacy, outcomes, and tolerance are unknown. METHODS AND RESULTS: Twelve patients (age 65 ± 9.7 years) were treated with ranolazine. Eleven (92%) were male, and 10 (83%) had ischemic heart disease with an average ejection fraction of 0.34 ± 0.13. All patients were on a class III AAD (11 amiodarone, one sotalol), with six (50%) receiving mexilitene or lidocaine. Five patients had a prior ablation and two were referred for a VT ablation at the index presentation. The QRS increased nonsignificantly from 128 ± 31 ms to 133 ± 31 ms, and the QTc increased nonsignificantly from 486 ± 32 ms to 495 ± 31 ms after ranolazine initiation. Over a follow-up of 6 ± 6 months, 11 (92%) patients had a significant reduction in VT and no ICD shocks were observed. VT ablation was not required in those referred. In two patients, gastrointestinal side effects limited long-term use. Of these two patients, one died due to progressive heart failure. In one patient, severe hypoglycemia limited dosing to 500 mg daily, but this was sufficient for VT control. CONCLUSION: Ranolazine proved effective in reducing VT burden and ICD shocks in patients with AAD-refractory VT. Ranolazine should be further tested for this indication and considered for clinical application when other options have proven ineffective.