The Use of Dual Chamber ICD With Special Programmed Features to Lower the Risk of Inappropriate Shock

Reduction And Prevention of Tachyarrhythmias and Shocks Using Reduced Ventricular Pacing With Atrial Algorithms (The RAPTURE Study)

The RAPTURE Study will determine whether dual chamber defibrillators with atrial prevention and termination therapies, minimized ventricular pacing, and remote monitoring will reduce the rate of inappropriate shocks and improve quality of life compared to optimally programmed back-up pacing only single chamber ICDs when used for primary prevention of sudden cardiac death

While implantable cardioverter-defibrillator (ICD) therapy has become the gold standard for sudden death prevention in high risk individuals, reduction of device associated morbidity remains a significant problem. Rapidly conducted atrial tachyarrhythmias inappropriately detected as ventricular tachycardia (VT) are the most common cause for inappropriate shocks in ICD recipients, affecting 10 to 40% of patients. Large multicenter trials have shown modest benefits of atrial pacing in preventing atrial fibrillation, however right ventricular (RV) pacing was not limited, thus any favorable effects associated with atrial prevention and treatment may have been offset by the RV pacing. New algorithms to prevent RV pacing are now made available in our current devices. The choice of dual chamber versus single chamber ICD for primary prevention warrants re-assessment of atrial prevention and termination therapies, without the potentially adverse effects of RV pacing.

This Multi Center Pilot study will enroll 100 eligible subjects, 50 to single chamber and 50 to dual chamber ICDs. Patients will be followed for one year.

Inclusion Criteria:

• Candidates for ICD for primary prevention according to American Heart Association/American College of Cardiology (AHA/ACC) guidelines who have a clinical indication for ICD implantation for ventricular arrhythmia or sudden death prevention.
• The ability to understand the scope of the study, provide written informed consent, and a willingness to complete all study visits and associated procedures.

Exclusion Criteria:

• Pregnant women
• Age <18 years old
• Inability to provide consent
• On a heart transplant waiting list
• Life expectancy <1 year
• Indication for pacing
• Atrioventricular (AV) node ablation
• Permanent atrial fibrillation or atrial flutter
• Indication for cardiac resynchronization
• Preexisting, separate pacemaker pulse generator that won't be explanted
• Intra-aortic balloon pump or other device
• Inotropic drug (not digitalis) necessary for hemodynamic support
• Chronic serious bacterial infection
• Inability to receive pectoral non-thoracotomy lead ICD
• Inability to program device according to protocol
• History of Out of Hospital Cardiac Arrest (OHCA) or sustained Ventricular Tachycardia as an indication for ICD (secondary prevention indication)