ROLE OF ANTITACHYCARDIA PACING IN PATIENT S WITH 3RD-GENERATION CARDIOVERTER-DEFIBRILLATORS

The most effective antitachycardia pacing mode (ATP) is still a matter of debate. Randomized prospective testing of 5 different ATP modes wa s performed in 82 patients (pts) prior to and after cardioverter defib rillator (ICD) implantation. The 5 ATP modes included 3-4 stimulation attempts with 4-10 adaptive scanning burst pulses. Adaptive burst coup ling interval was 75 % in mode A, 81 % in mode B, 69 % in mode C, 72 % in mode D, and 88 % in mode E. Autodecremental scanning within bursts was 8 ms in modi A, B, and C, and 10 ms in modus E; autodecremental s canning between bursts was 8 ms in modi B and C, and 10 ms in modus D. During the pre-op electrophysiologic study (EP), termination (TR) of induced ventricular tachycardia (VT) was possible in 69 % and by pre-d ischarge EP in 53 %. Acceleration (AC) rates were 16 % pre-op and 32 % post-op (p = ns). There were no significant differences in TR or AC b etween modes A-E. During a mean follow-up of 18 +/- 4 (< 1-41) months, 3182 arrhythmia episodes (AE) occurred: 344 AE (11 %) were terminated by primary ICD shocks and ATP was attempted in 2838 AE (89 %) and was successful in 2576 AE (91 %). AC occurred in 87 AE (3 %) and ATP was without effect in 175 AE (6 %). Our data show that ATP is helpful in p atients with third-generation ICDs and is very effective during follow -up. However, there is no ideal ATP-mode visible in the present study.