Modi Simon, Krahn Andrew, Yee Raymond
Arrhythmia Service, London Health Sciences Centre, London, ON, Canada,
Curr Treat Options Cardiovasc Med. 2011 Oct;13(5):370-84. doi: 10.1007/s11936-011-0137-6.
Over five decades have passed since the first permanent cardiac pacemakers were introduced into clinical medicine. Evolving technology and falling costs have demanded adaptation to clinical practice and implantation trends and, with the advent of evidenced-based medicine, the specific roles and benefits of individual pacemaker technologies have never been so carefully scrutinized. Pacing mode choice continues to be a subject of great controversy, and there are great regional variations in practice. We believe that single chamber atrial pacing use (AAI/R) has become an anachronism that should generally be abandoned (obviously with rare exceptional cases) and be replaced by dual chamber pacemakers (DDD/R) equipped with modern pacing algorithms that minimize patient exposure to ventricular pacing. Also, in patients with atrioventricular (AV) block, randomized clinical trials have failed to show improvement in clinically relevant outcomes such as mortality, stroke, and heart failure, particularly in the elderly, which has led some to advocate that DDD/R devices should never be offered to elderly AV block patients. However, we believe that the elderly, like the young, come in many "shapes and sizes" and individualized medicine compels us to consider each pacemaker candidate as unique. Implanting DDD/R devices in chronologically older, yet physiologically younger, patients is justifiable and good medical practice. Where right ventricular (RV) pacing is necessary and unavoidable, physicians should consider routinely placing RV leads on the RV mid- or outflow tract septum because these location are as good, if not better, for patients than the current practice of RV apical lead placement. In patients with AV block and asymptomatic yet moderate to severely depressed left ventricular systolic function, primary cardiac resynchronization therapy (CRT) should be strongly considered. Compelling clinical trial evidence does not yet exist to indicate that CRT should be the standard of care in patients with AV block and intact left ventricular systolic function. Right ventricular septal lead placement remains a reasonable option.
自首个永久性心脏起搏器应用于临床医学至今,已过去五十多年。技术的不断发展以及成本的降低,要求我们适应临床实践和植入趋势。随着循证医学的出现,各种心脏起搏器技术的具体作用和益处从未受到如此细致的审视。起搏模式的选择仍然是一个极具争议的话题,而且在实际应用中存在很大的地区差异。我们认为,单腔心房起搏(AAI/R)已变得不合时宜,一般应予以摒弃(显然存在极少数例外情况),取而代之的是配备现代起搏算法的双腔起搏器(DDD/R),这种算法可将患者接受心室起搏的情况降至最低。此外,在患有房室(AV)传导阻滞的患者中,随机临床试验未能显示在死亡率、中风和心力衰竭等临床相关结局方面有所改善,尤其是在老年患者中,这使得一些人主张永远不应为老年AV传导阻滞患者提供DDD/R设备。然而,我们认为,老年人和年轻人一样,存在多种不同情况,个体化医疗促使我们将每个起搏器候选者视为独特个体。在按年龄计算年长但生理状态较年轻的患者中植入DDD/R设备是合理的,也是良好的医疗实践。在右心室(RV)起搏必要且不可避免的情况下,医生应考虑常规将RV导线置于RV中间或流出道间隔,因为这些位置对患者来说即便不比当前将RV导线置于心尖的做法更好,至少也是一样好。对于患有AV传导阻滞且左心室收缩功能无症状但中度至重度降低的患者,应强烈考虑进行心脏再同步化治疗(CRT)。目前尚无令人信服的临床试验证据表明CRT应成为AV传导阻滞且左心室收缩功能正常患者的标准治疗方法。将RV导线置于室间隔仍是一个合理的选择。