Neglia J J, Krol R B, Giorgberidze I, Mathew P, Lewis C, Munsif A N, Saksena S
Arrhythmia and Pacemaker Service, Eastern Heart Institute, Passaic, New Jersey, USA.
J Interv Card Electrophysiol. 1997 Feb;1(1):49-56. doi: 10.1023/a:1009766718942.
The clinical efficacy of electrical algorithms for termination of slow ventricular tachycardia (VT) and ventricular fibrillation (VF) in implantable cardioverter-defibrillators (ICDs) is well established. Such algorithms have not been equally well defined for fast VT reversion. We report the testing of a prospectively designed algorithm for ICDs to treat fast VT that is inherently less responsive to antitachycardia pacing than slow VT. Fourth-generation ICD devices were programmed to three prospectively defined tachycardia detection zones as follows: cycle lengths < or = 260 ms for VF, 270-330 ms for fast VT, and > 330 ms for slow VT. The initial selected therapy for the VF zone was a high-energy biphasic shock (> 15 J), while a 3- or 5-J biphasic shock was usually administered for fast VT, and antitachycardia pacing was initially attempted for slow VT. Initial therapy was followed by backup therapy with high-energy shocks. Twenty-eight patients, 24 of whom were males, all with organic heart disease, with a mean age of 65 +/- 9 years, received either a Medtronic 7219D (23 patients), 7219C (2 patients), 7218SP1 (2 patients), or 7218C (1 patient) ICD with a nonthoracotomy lead system. The defibrillation threshold was 10 +/- 5 J. At predischarge electrophysiologic testing, a single 3- or 5-J shock terminated all episodes of fast VT tested. During a follow-up of 18 +/- 9 months, there were four nonarrhythmic deaths. Fourteen patients (50%) had a total of 21 VF, 44 fast VT, and 202 slow VT episodes. Twenty-three of 24 (96%) VF, 33 of 39 (84%) fast VT, and 193 of 202 (95.5%) slow VT episodes were terminated with the first delivered therapy in each therapy algorithm (p = NS). The overall efficacy of the entire electrical therapy algorithm was 100% for VF, 100% for fast VT, and 98% for slow VT episodes (p = NS). No patient experienced syncope or presyncope during fast VT or VF in this study. We conclude that a third detection and therapy zone can be successfully programmed in ICDs to define a range of fast VT episodes that can be effectively terminated with lower energy cardioversion shocks with comparable success and freedom from arrhythmic symptoms to electrical therapies used for slow VT and VF.
植入式心脏复律除颤器（ICD）中用于终止缓慢型室性心动过速（VT）和心室颤动（VF）的电算法的临床疗效已得到充分证实。但对于快速型VT的转复，此类算法尚未得到同样明确的定义。我们报告了一种针对ICD治疗快速型VT的前瞻性设计算法的测试情况，该算法对心动过速起搏的反应天生就比缓慢型VT低。第四代ICD设备被编程设置为三个前瞻性定义的心动过速检测区，具体如下：VF时周长≤260毫秒，快速型VT时周长为270 - 330毫秒，缓慢型VT时周长＞330毫秒。VF区的初始选定治疗方法是高能量双相电击（＞15焦耳），而快速型VT通常给予3焦耳或5焦耳的双相电击，缓慢型VT则首先尝试进行抗心动过速起搏。初始治疗后采用高能量电击作为备用治疗。28例患者，其中24例为男性，均患有器质性心脏病，平均年龄65±9岁，接受了美敦力7219D（23例患者）、7219C（2例患者）、7218SP1（2例患者）或7218C（1例患者）的ICD及非开胸导联系统。除颤阈值为10±5焦耳。在出院前的电生理测试中，单次3焦耳或5焦耳的电击终止了所有测试的快速型VT发作。在18±9个月的随访期间，有4例非心律失常性死亡。14例患者（50%）共发生21次VF、44次快速型VT和202次缓慢型VT发作。在每种治疗算法中，24次VF发作中的23次（96%）、39次快速型VT发作中的33次（84%）以及202次缓慢型VT发作中的193次（95.5%）在首次给予治疗时就被终止（p = 无显著性差异）。整个电治疗算法对VF发作的总体疗效为100%，对快速型VT发作的总体疗效为100%，对缓慢型VT发作的总体疗效为98%（p = 无显著性差异）。在本研究中，没有患者在快速型VT或VF期间经历晕厥或接近晕厥的情况。我们得出结论，ICD中可以成功编程设置第三个检测和治疗区，以定义一系列快速型VT发作，这些发作可以用较低能量的心脏复律电击有效终止，其成功率和无心律失常症状的程度与用于缓慢型VT和VF的电疗法相当。
