Henry Ford Heart & Vascular Institute, Detroit, Michigan.
Division of Cardiology, Duke University Medical Center, Durham, North Carolina.
Heart Rhythm. 2021 Mar;18(3):399-403. doi: 10.1016/j.hrthm.2020.11.019. Epub 2020 Nov 21.
In Multicenter Automatic Defibrillator Implantation Trial - Reduce Inappropriate Therapy (MADIT-RIT), high-rate cutoff (arm B) and delayed therapy (arm C) reduced the risk of inappropriate implantable cardioverter-defibrillator (ICD) interventions when compared with conventional programming (arm A); however, appropriate but unnecessary therapies were not evaluated.
The purpose of this study was to assess the value of antitachycardia pacing (ATP) for fast ventricular arrhythmias (VAs) ≥ 200 beats/min in patients with primary prevention ICD.
We compared ATP only, ATP and shock, and shock only rates in patients in MADIT-RIT treated for VAs ≥ 200 beats/min. The only difference between these randomized groups was the time delay between ventricular tachycardia detection and therapy (3.4 seconds vs 4.9 seconds vs 14.4 seconds).
In arm A, 11.5% patients had events, the initial therapy was ATP in 10.5% and shock in 1%, and the final therapy was ATP in 8% and shock in 3.5%. In arm B, 6.6% had events, 4.2% were initially treated with ATP and 2.4% with shock, and the final therapy was ATP in 2.8% and shock in 3.8%. In arm C, 4.7% had events, 2.5% were initially treated with ATP and 2.3% with shock, and the final therapy was ATP in 1.4% and shock in 3.3%. The final shock rate was similar in arm A vs arm B (3.5% vs 3.8%; P = .800) and in arm A vs arm C (3.5% vs 3.3%; P = .855) despite the marked discrepancy in initial ATP therapy utilization.
In MADIT-RIT, there was a significant reduction in ATP interventions with therapy delays due to spontaneous termination, with no difference in shock therapies, suggesting that earlier interventions for VAs ≥ 200 beats/min are likely unnecessary, leading to an overestimation of the value of ATP in primary prevention ICD recipients.
在多中心自动除颤器植入试验-降低不适当治疗（MADIT-RIT）中，与传统编程（A 臂）相比，高心率截止（B 臂）和延迟治疗（C 臂）降低了植入式心脏复律除颤器（ICD）不适当干预的风险；然而，并未评估适当但不必要的治疗。
本研究旨在评估抗心动过速起搏（ATP）在原发性预防 ICD 患者中对≥200 次/分的快速室性心律失常（VA）的价值。
我们比较了 MADIT-RIT 中治疗≥200 次/分的 VA 患者中仅 ATP、ATP 和电击以及仅电击的治疗率。这些随机分组之间唯一的区别是室性心动过速检测和治疗之间的时间延迟（3.4 秒对 4.9 秒对 14.4 秒）。
在 A 臂中，11.5%的患者发生事件，初始治疗为 ATP 的占 10.5%，电击的占 1%，最终治疗为 ATP 的占 8%，电击的占 3.5%。在 B 臂中，6.6%的患者发生事件，4.2%的患者最初接受 ATP 治疗，2.4%的患者接受电击治疗，最终治疗为 ATP 的占 2.8%，电击的占 3.8%。在 C 臂中，4.7%的患者发生事件，2.5%的患者最初接受 ATP 治疗，2.3%的患者接受电击治疗，最终治疗为 ATP 的占 1.4%，电击的占 3.3%。尽管初始 ATP 治疗的应用存在明显差异，但 A 臂与 B 臂（3.5%比 3.8%；P =.800）和 A 臂与 C 臂（3.5%比 3.3%；P =.855）的最终电击率相似，这表明由于自发性终止，治疗延迟导致 ATP 干预显著减少，提示对于≥200 次/分的 VA，早期干预可能是不必要的，这导致了对原发性预防 ICD 接受者中 ATP 价值的高估。
