Wolber Thomas, Binggeli Christian, Holzmeister Johannes, Brunckhorst Corinna, Strobel Ulla, Boes Claudia, Moser Ray, Becker Daniel, Duru Firat
Cardiovascular Center, Cardiology, University Hospital Zurich, Zurich, Switzerland.
Pacing Clin Electrophysiol. 2006 Nov;29(11):1255-60. doi: 10.1111/j.1540-8159.2006.00521.x.
Inappropriate therapy delivery is an important concern in the management of patients with implantable cardioverter defibrillators (ICDs). Recently, a morphology-based algorithm (wavelet feature) has been introduced for differentiation of ventricular and supraventricular tachycardia. In this study, we evaluated the performance of the wavelet algorithm using various electrogram (EGM) configurations during different body positions.
Patients with a single-chamber Medtronic model 7230 ICD (Minneapolis, MN, USA) and a double-coil lead were included. EGM templates were collected during baseline rhythm in supine position for different EGM sources (right ventricular [RV] coil-can, RV coil-superior vena cava [SVC] coil, tip-ring, SVC coil-can). For each EGM configuration, morphologic similarity (match percentage) of EGMs obtained during different body positions (supine, left and right lateral, sitting, standing, walking) were compared with the templates.
Twenty-eight patients (24 males; age 58 +/- 17 years) were studied. A total of 9,775 intracardiac EGMs were analyzed. Median match percentage (interquartile range) was 88% (85-94), 88% (82-94), 82% (76-88), and 73 (58-85) for the RV coil-can, RV coil-SVC coil, tip-ring, and SVC coil-can configurations, respectively. Correct classification rates, as defined by match percentage of 70% or higher, were significantly higher with the RV coil-can, RV coil-SVC coil, and tip-ring EGM configurations, as compared to the SVC coil-can configuration (95, 91, and 91 vs 58% > or =70% match percent, P < 0.001).
Wavelet-based morphology scores in ICDs may change with various body positions. These variations are relatively minor using the nominal configuration (RV coil-can), as well as by using RV coil-SVC coil and tip-ring. However, morphology scores can vary considerably when SVC coil-can is used; therefore, this configuration should be avoided while using the wavelet algorithm.
在植入式心脏复律除颤器（ICD）患者的管理中，不适当的治疗交付是一个重要问题。最近，一种基于形态学的算法（小波特征）已被引入用于区分室性和室上性心动过速。在本研究中，我们评估了小波算法在不同体位下使用各种心内电图（EGM）配置的性能。
纳入使用美敦力7230单腔ICD（美国明尼阿波利斯）和双线圈导线的患者。在仰卧位的基线心律期间，针对不同的EGM来源（右心室[RV]线圈-罐、RV线圈-上腔静脉[SVC]线圈、尖端-环、SVC线圈-罐）收集EGM模板。对于每种EGM配置，将在不同体位（仰卧、左侧和右侧卧位、坐位、站立位、行走位）获得的EGM的形态相似性（匹配百分比）与模板进行比较。
研究了28例患者（24例男性；年龄58±17岁）。共分析了9775份心内EGM。RV线圈-罐、RV线圈-SVC线圈、尖端-环和SVC线圈-罐配置的中位匹配百分比（四分位间距）分别为88%（85-94）、88%（82-94）、82%（76-88）和73（58-85）。与SVC线圈-罐配置相比，RV线圈-罐、RV线圈-SVC线圈和尖端-环EGM配置的正确分类率（定义为匹配百分比≥70%）显著更高（95%、91%和91%对58%≥70%匹配百分比，P<0.001）。
ICD中基于小波的形态学评分可能随不同体位而变化。使用标称配置（RV线圈-罐）以及RV线圈-SVC线圈和尖端-环时，这些变化相对较小。然而，当使用SVC线圈-罐时，形态学评分可能有很大差异；因此，在使用小波算法时应避免这种配置。
