双腔埋藏式心脏复律除颤器

Dual Chamber Implantable Cardioverter Defibrillator (ICD).

双腔埋藏式心脏复律除颤器 (ICD)可提供起搏及抗室性和房性心律失常的治疗。报道 11例双腔ICD应用的临床体会。男 8例、女 3例 ,年龄 6 0 .5 5± 10 .0 7岁。缺血性心脏病 9例、Brugada综合征 1例、缺血性心脏病合并肥厚型梗阻性心脏病 1例。双腔ICD安置指征有 :室上性快速心律失常伴室性快速心律失常 6例 ,室性快速性心律失常伴房室阻滞 1例、伴左室功能不全 4例 ;临床上明确记录到室性心动过速 (简称室速 )、心室颤动 (简称室颤 )和室上性快速心律失常者分别为 8,2和 5例。 8例病人术前进行电生理检查 ,诱发出持续性室速 6例、室颤 2例 ;3例行电生理检查 ,其中 2例太虚弱、1例为反复发作持续性室速。 5例安置具有心室转复除颤伴心房、心室起搏的ICD ,5例安置具有心房、心室起搏转复及除颤的ICD ,1例安置具有双心室起搏及心室转复、除颤的ICD。所有病人在置入ICD时都进行除颤阈值的测定。总共有 2 3次室颤被诱发 ,除颤阈值为 12 .0 9± 5 .2 4J,除颤电极阻抗为 44 .0 0±11.0 5Ω ,P波和R波电压幅度分别为 3.5 3± 1.32mV ,13.42± 4.73mV ,心房、心室起搏阈值分别为 1.39± 0 .71和 0 .91± 0 .38V。随访 8.82± 5 .0 0 (2～ 19)个月 ,5例共有 12 0次持续性室速发生 ,其中 118次经抗心动过速起搏成功?

Dual chamble ICD provides bradycardia rate responsive pacing therapy in the atrial and ventricular tachyarrhythmia therapy in the ventricle and/or in the atrium.We report our initial experience of clinical performance of dual chamber ICDs in National Heart Centre,Singapore.Methods:From July 1998 to February 2000,patients (pts) with dual chamber ICD implanted were followed up regularly clinically and with interrogation of the device.Results:There were 11 pts (8 males) with a mean age of 60.55±10.07(47～81) years.The underlying diagnoses were ischemic heart disease (IHD) (9),Brugada syndrome (1) and ischemic heart disease with hypertrophic obstructive cardiomyopathy(HOCM) (1).The indication for dual chamber ICD were the presence of superventricular tachyarrhythmia (SVT) and ventricular tachyarrhythmia(VTA) (6),atrioventricular(AV) block/VTA (1),VTA with poor left ventricular function (4).Clinically documented ventricular tachycardia(VT),ventricular fibrillation(VF) and SVT were noted in 8,2 and 5 pts respectively.Eight pts had undergone eletrophysiology studys (EPS) prior to implantation of ICD (6 with sustained VT and 2 VF),3 pts were not done EPS.2 pts were too sick and 1 pt had frequent sustained VT.There were 3 types of devices implanted:ventricular ICD with dual chamber pacing (5),atrial and ventricular defibrillator (5) and biventricular pacemaker and ICD (1).All pts had defibrillation thresholds (DFT) determined at implantation.A total of 23 episodes of VF were induced at implantation with mean DFT 12.09±5.24 J.The average shocking impedance was 44±11.05 Ω,the mean acute P wave measured 3.53 ±1.32 mV and R wave measured 13.42±4.73 mV.Atrial and ventricular thresholds at pulse width 0.5 ms averaged 1.39 ± 0.71 V and 0.91±0.38 V.During following up 8.82±5.00 (2～19) months.Five pts had arrhythmic events with 120 sustained VT episodes of which 118 were treated successfully with anti tachycardia pacing (ATP) and 2 required DC shock by device.1 pt required radiofrequency(RF) ablation because of frequent sustained VT.There were 1 VF,2 AT and 1 heart block episodes which were successfully treated by the device with DC shock,ATP and DDD pacing,respectively.Two pts had atrial fibrillation(AF) but were not given DC shock.There was no inappropriate discharge of the device.One pt who had CAD and paroxsymal Af for 15 years,suffered a stroke a week after implantation of ICD.But he is still alive.Conclusions:Dual chamber ICD provides atrioventricular association and promotes reliable defibrillation by differentiating ventricular and supraventricular tachycardia,and therefore reduces the incidence of inappropriate discharge.It is a relatively safe device to implant and effective in terminating SVT and VT in our pts.