UCLA Cardiac Arrhythmia Center, Ronald Reagan UCLA Medical Center, Los Angeles, CA 90095, USA.
Europace. 2011 May;13(5):683-8. doi: 10.1093/europace/euq519. Epub 2011 Jan 19.
The utility of defibrillation threshold testing in patients undergoing implantable cardioverter-defibrillator (ICD) implantation is controversial. Higher defibrillation thresholds have been noted in patients undergoing implantation of cardiac resynchronization therapy defibrillators (CRT-D). Since the risks and potential benefits of testing may be higher in this population, we sought to assess the impact of defibrillation safety margin or vulnerability safety margin testing in CRT-D recipients.
A total of 256 consecutive subjects who underwent CRT-D implantation between January 2003 and December 2007 were retrospectively reviewed. Subjects were divided into two groups based on whether (n= 204) or not (n= 52) safety margin testing was performed. Patient characteristics, tachyarrhythmia therapies, procedural results, and clinical outcomes were recorded. Baseline characteristics, including heart failure (HF) severity, were comparable between the groups. Four cases of HF exacerbation (2%), including one leading to one death, were recorded in the tested group immediately post-implantation. No complications were observed in the untested group. After a mean follow-up of 32 ± 20 months, the proportion of appropriate shocks in the two groups was similar (31 vs. 25%, P = 0.49). There were three cases of failed appropriate shocks in the tested group, despite adequate safety margins at implantation, whereas no failed shocks were noted in the untested group. Survival was similar in the two groups.
Defibrillation efficacy testing during implant of CRT-D was associated with increased morbidity and did not predict the success of future device therapy or improve survival during long-term follow-up.
在植入植入式心脏复律除颤器（ICD）的患者中，除颤阈值测试的实用性存在争议。在接受心脏再同步治疗除颤器（CRT-D）植入的患者中，已经注意到更高的除颤阈值。由于在该人群中测试的风险和潜在益处可能更高，我们试图评估 CRT-D 接受者的除颤安全裕度或脆弱性安全裕度测试的影响。
回顾性分析了 2003 年 1 月至 2007 年 12 月期间接受 CRT-D 植入的 256 例连续患者。根据是否进行安全裕度测试（n=204）或未进行安全裕度测试（n=52）将患者分为两组。记录患者特征、快速性心律失常治疗、程序结果和临床结局。两组基线特征，包括心力衰竭（HF）严重程度，均具有可比性。在测试组中，植入后立即记录到 4 例 HF 恶化（2%），包括 1 例导致死亡。未在未测试组中观察到任何并发症。平均随访 32±20 个月后，两组的适当电击比例相似（31%比 25%，P=0.49）。尽管在植入时具有足够的安全裕度，但在测试组中有 3 例适当电击失败，而在未测试组中则没有。两组的存活率相似。
在 CRT-D 植入期间进行除颤效果测试与发病率增加有关，并且不能预测未来设备治疗的成功或改善长期随访期间的生存。
