Clinical experience with a tiered-therapy, multiprogrammable antiarrhythmia device.

Abstract

BACKGROUND The purpose of this report is to describe our initial experience with a tiered-therapy, variable detection criteria, multiprogrammable antiarrhythmia device capable of antitachycardia pacing, cardioversion, and defibrillation in 50 cardiac arrest survivors. METHODS AND RESULTS An epicardial lead system was used in 35 patients. A transvenous lead system was used in 15 patients. The index arrhythmia leading to device implantation was ventricular fibrillation (VF) in 23 patients, ventricular tachycardia (VT) in 21 patients, and both VT and VF in six patients. Postoperatively, all 50 patients benefited from the additional functions available in the new device compared with a device capable only of high-energy termination of arrhythmias using a simple rate detection algorithm. Total patient survival over a mean follow-up period of 15 +/- 5 months was 96%, with no patient succumbing to sudden arrhythmic death, cardiac death, or surgical death. Nine patients (18%) avoided the need for a bradycardia pacemaker because of the device's backup bradycardia pacing function. A programmable tachycardia cycle length stability algorithm prevented inappropriate device intervention into atrial fibrillation in 11 patients (22%). Detection schema flexibility, antitachycardia pacing capabilities, and low-energy cardioversion options allowed the elimination or avoidance of antiarrhythmic drugs in 41 patients (82%). Device data storage facilitated troubleshooting and reprogramming of detection algorithms and therapeutic schema in all 50 patients. Finally, the ability to perform noninvasive programmed electrical stimulation obviated the need for invasive cardiac catheterization in 35 of 35 patients who required electrophysiological testing after device implantation. CONCLUSIONS These findings indicate that a multiprogrammable antiarrhythmia device can provide a substantial advance in the treatment of patients with disabling or life-threatening ventricular arrhythmias by minimizing the use of painful shocks, reducing the need for antiarrhythmic drugs, lowering the incidence of inappropriate shocks, facilitating electrophysiological evaluation, and obviating the need for dual-device therapy.