Pilot Study of Catheter Ablation for Ventricular Tachycardia in Patients With an Implantable Cardioverter Defibrillator

Catheter Ablation for Ventricular Tachycardia in Patients With an Implantable Cardioverter Defibrillator (CALYPSO) PILOT TRIAL

The purpose of this pilot trial is to determine the feasibility of a large, multi-center randomized clinical trial aimed to test whether a treatment strategy of percutaneous catheter ablation of ventricular tachycardia (VT) is superior to state-of-the-art pharmacologic therapy at reducing all-cause mortality in patients with an implantable cardioverter defibrillator (ICD) who receive therapy for VT in the absence of any reversible cause.

This study will be conducted at up to 8 sites and will randomize 50 patients over 1 year to a strategy of catheter ablation (n=25) vs. state-of-the-art pharmacologic therapy (n=25). To be considered for enrollment in this pilot trial, patients must be at least 18 years of age and must have an ICD for a primary or secondary prevention indication, have ≥ 1 documented ICD shock or ≥ 3 ATP therapies for VT in the absence of a reversible cause that in the opinion of the treating physician requires further therapy and be eligible for both catheter ablation and at least 1 antiarrhythmic medication. Patients will be followed at 3 and 6 months and their vital status will be determined via a phone call at 12 months. Data on the safety and efficacy of therapies used in the pilot study will be collected. Of particular interest are adverse events resulting from the catheter ablation procedure and major side effects from antiarrhythmic medications.

Inclusion Criteria:

• Have an ICD with or without cardiac resynchronization therapy (i.e. CRT-D) for a primary or secondary prevention indication
• Have ischemic heart disease defined as the presence of wall motion abnormalities and documented coronary artery disease (one ≥ 70% stenosis in ≥ 1 major coronary artery)
• Have ≥ 1 documented ICD shock or ≥ 3 ATP therapies within 6 months before randomization for VT in the absence of a reversible cause that in the opinion of the treating physician requires further therapy. The VT has to be monomorphic and at a rate of ≤ 260 bpm.
• Be at least 18 years of age
• Be eligible for catheter ablation
• Have no history of intolerance or contraindication to at least 1 of the following antiarrhythmic medications: amiodarone, sotalol, and mexiletine.

Exclusion:

• Patients who in the opinion of the treating physician should not receive additional therapy
• More than 30 days of amiodarone treatment in the past 3 months unless the patient has been on ≤ 200 mgs of amiodarone daily for atrial arrhythmias or premature ventricular contractions (PVCs) and the patient is eligible for a higher dose of amiodarone
• Incessant VT that necessitates immediate treatment
• Reversible causes of VT including but not limited to ischemia, decompensated HF, and electrolyte disturbances
• The presence of a contraindication to catheter ablation of VT (including the presence of a mobile ventricular thrombus; an acute MI, coronary revascularization, or a stroke in the preceding 30 days; unstable angina or NYHA class IV HF; a mechanical valve; or inability to receive anticoagulation or antithrombotic therapy)
• Patients with non-ischemic cardiomyopathy
• Patients with hypertrophic obstructive, restrictive, or infiltrative cardiomyopathy
• Patients with acute myocarditis, congenital heart disease, valvular disease likely to require surgery in the next 1 year, and/or inoperable obstructive valvular disease
• Patients with a heart transplant or who are expected to undergo cardiac transplantation within 12 months
• Patients with a left ventricular assist device
• Patients who are already on antiarrhythmic drug therapy (other than beta-blockers) for VT (patients will not be excluded if they are receiving antiarrhythmic drug therapy for atrial arrhythmias or PVCs if they are eligible for additional drug therapy for VT).
• Heritable arrhythmias or increased risk for torsade de pointes with class III drugs
• End stage renal disease requiring dialysis
• Estimated life expectancy of <1 year from a non-cardiac cause
• Women who are pregnant or who have childbearing potential and are not using a reliable method of contraception
• Inability to give informed consent