Catheter Ablation Versus Amiodarone for Shock Prophylaxis in Defibrillator Patients With Ventricular Tachycardia

Implantable Cardioverter Defibrillators (ICDs) provide a shock or pacing therapy to bring back a normal heart beat when a patient experiences a dangerous abnormal heart rhythm such as ventricular tachycardia (VT). ICDs are very successful in bringing back a normal heart beat when VT occurs, but they do not prevent further dangerous heart rhythms from occurring. This study is designed to determine the best way to manage patients who have an ICD and who continue to have episodes of VT. There are two methods for treatment the VT: 1) Ablation, and 2) Medication. An ablation procedure involves placing a flexible catheter (insulated wire) in the groin area and threading it into the heart. After the doctor has located the affected area responsible for the VT, radiofrequency energy is delivered by the power generator through the catheter to the inside of the heart. The radiofrequency energy ablates (burns) a small area of the heart tissue thought to cause the VT. A medication called Amiodarone is an "anti-arrhythmic" prescribed to prevent abnormal heart rhythms from recurring. The purpose of this study is to compare these two different methods for treating VT. Treatment with ablation and amiodarone are both considered the standard of care for patients with VT but they have not been compared directly in a study like this before.