EXPERIENCE WITH 3 DIFFERENT 3RD-GENERATION CARDIOVERTER-DEFIBRILLATORS IN PATIENTS WITH CORONARY-ARTERY DISEASE OR CARDIOMYOPATHY

Clinical investigations are being performed in multiprogrammable devices whose therapeutic options include antitachycardia pacing, cardioversion, defibrillation and bradycardia pacing. Three different third-generation devices were implanted in 46 research patients at 1 clinical center to document their safety and efficacy for the treatment of malignant ventricular arrhythmias. Additionally, the purpose of the study was to determine if antitachycardia pacing is a desirable and frequently used feature of tiered devices. The Medtronic PCD was implanted in 15 patients (12 men, mean age 60 +/- 13 years, mean ejection fraction 40 +/- 15%), the Ventritex Cadence in 21 patients (17 men, mean age 65 +/- 10 years, mean ejection fraction 38 +/- 12%), and the CPI VENTAK PRx in 10 patients (8 men, mean age 63 +/- 14 years, mean ejection fraction 31 +/- 8%). All patients presented with cardiac arrest or ventricular tachycardia. During follow-up of 10 +/- 6 months (range 1 to 19), 70% of the 20 patients with antitachycardia pacing activated used the feature for spontaneous ventricular tachycardia. The antitachycardia pacing parameters were reprogrammed 20 times in 15 patients. Two thousand six hundred thirty-eight of 2,675 (98%) antitachycardia pacing attempts successfully terminated spontaneous tachyarrhythmias. Low-energy cardioversion or defibrillation terminated tachyarrhythmias in patients where pacing was unsuccessful. One hundred forty-eight episodes of tachycardia were successfully treated directly by shocks in 16 of 46 patients (35%). There were no deaths due to device failure. This initial single-center clinical experience suggests that the PCD, Cadence and VENTAK PRx are all safe and effective tiered therapy devices for the treatment of malignant ventricular arrhythmias. Antitachycardia pacing successfully terminated most episodes of ventricular tachycardia; in patients with this feature activated, it was used frequently but required reprogramming to achieve high levels of success.