[The role of anti-tachycardia stimulation in patients with 3rd-generation defibrillators]

The most effective antitachycardia pacing mode (ATP) is still a matter of debate. Randomized prospective testing of 5 different ATP modes was performed in 82 patients (pts) prior to and after cardioverter defibrillator (ICD) implantation. The 5 ATP modes included 3-4 stimulation attempts with 4-10 adaptive scanning burst pulses. Adaptive burst coupling interval was 75% in mode A, 81% in mode B, 69% in mode C, 72% in mode D, and 88% in mode E. Auto-decremental scanning within bursts was 8 ms in modi A, B, and C, and 10 ms in modus E; autodecremental scanning 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-discharge 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 between 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 patients with third-generation ICDs and is very effective during follow-up. However, there is no ideal ATP-mode visible in the present study.