Day John D, Doshi Rahul N, Belott Peter, Birgersdotter-Green Ulrika, Behboodikhah Mahnaz, Ott Peter, Glatter Kathryn A, Tobias Serge, Frumin Howard, Lee Byron K, Merillat John, Wiener Isaac, Wang Samuel, Grogin Harlan, Chun Sung, Patrawalla Rob, Crandall Brian, Osborn Jeffrey S, Weiss J Peter, Lappe Donald L, Neuman Stacey
Utah Heart Clinic Arrhythmia Service, LDS Hospital, 324 10th Ave, #206, Salt Lake City, UT 84103, USA.
Circulation. 2007 May 8;115(18):2382-9. doi: 10.1161/CIRCULATIONAHA.106.663112. Epub 2007 Apr 30.
Implantable cardioverter-defibrillators and cardiac resynchronization therapy defibrillators have relied on multiple ventricular fibrillation (VF) induction/defibrillation tests at implantation to ensure that the device can reliably sense, detect, and convert VF. The ASSURE Study (Arrhythmia Single Shock Defibrillation Threshold Testing Versus Upper Limit of Vulnerability: Risk Reduction Evaluation With Implantable Cardioverter-Defibrillator Implantations) is the first large, multicenter, prospective trial comparing vulnerability safety margin testing versus defibrillation safety margin testing with a single VF induction/defibrillation.
A total of 426 patients receiving an implantable cardioverter-defibrillator or cardiac resynchronization therapy defibrillator underwent vulnerability safety margin or defibrillation safety margin screening at 14 J in a randomized order. After this, patients underwent confirmatory testing, which required 2 VF conversions without failure at < or = 21 J. Patients who passed their first 14-J and confirmatory tests, irrespective of the results of their second 14-J test, had their devices programmed to a 21-J shock for ventricular tachycardia (VT) or VF > or = 200 bpm and were followed up for 1 year. Of 420 patients who underwent 14-J vulnerability safety margin screening, 322 (76.7%) passed. Of these, 317 (98.4%) also passed 21-J confirmatory tests. Of 416 patients who underwent 14-J defibrillation safety margin screening, 343 (82.5%) passed, and 338 (98.5%) also passed 21-J confirmatory tests. Most clinical VT/VF episodes (32 of 37, or 86%) were terminated by the first shock, with no difference in first shock success. In all observed cases in which the first shock was unsuccessful, subsequent shocks terminated VT/VF without complication.
Although spontaneous episodes of fast VT/VF were limited, there was no difference in the odds of first shock efficacy between groups. Screening with vulnerability safety margin or defibrillation safety margin may allow for inductionless or limited shock testing in most patients.
植入式心脏复律除颤器（ICD）和心脏再同步治疗除颤器（CRT-D）在植入时依赖多次室颤（VF）诱发/除颤测试，以确保设备能够可靠地感知、检测并转复VF。ASSURE研究（心律失常单次电击除颤阈值测试与易损性上限：植入式心脏复律除颤器植入的风险降低评估）是第一项大型、多中心、前瞻性试验，比较了单次VF诱发/除颤的易损性安全边际测试与除颤安全边际测试。
共有426例接受ICD或CRT-D的患者以随机顺序接受了14焦耳的易损性安全边际或除颤安全边际筛查。在此之后，患者接受确认性测试，该测试要求在≤21焦耳时两次VF转复均无失败。通过首次14焦耳和确认性测试的患者，无论其第二次14焦耳测试结果如何，其设备被程控为针对室性心动过速（VT）或心率≥200次/分钟的VF发放21焦耳电击，并随访1年。在420例接受14焦耳易损性安全边际筛查的患者中，322例（76.7%）通过。其中，317例（98.4%）也通过了21焦耳确认性测试。在416例接受14焦耳除颤安全边际筛查的患者中，343例（82.5%）通过，338例（98.5%）也通过了21焦耳确认性测试。大多数临床VT/VF发作（37例中的32例，即86%）被首次电击终止，首次电击成功率无差异。在所有首次电击未成功的观察病例中，后续电击均成功终止VT/VF且无并发症。
尽管快速VT/VF的自发发作有限，但两组间首次电击疗效的几率无差异。采用易损性安全边际或除颤安全边际进行筛查可能使大多数患者无需诱发或仅需有限的电击测试。
