Rami Tapan, Shih Hue-Teh
Division of Cardiology, Department of Medicine, Baylor College of Medicine, Houston, Texas 77030, USA.
Curr Opin Cardiol. 2004 May;19(3):264-9. doi: 10.1097/00001573-200405000-00012.
Heart failure prevalence is reaching epidemic proportion in the United States and is associated with significant morbidity and mortality. A large proportion of the mortality is the result of sudden cardiac death (SCD). Clinical trials have demonstrated the superiority of the implantable cardioverter/defibrillator (ICD) compared with antiarrhythmic drugs for secondary prevention of sudden cardiac death.
Recently, several clinical trials in primary prevention of sudden cardiac death in both ischemic and nonischemic heart failure have been completed. The 2002 guidelines for implantable cardioverter/defibrillator implantation were recently released as well. Adjunct therapy consisting of antiarrhythmic drugs or radiofrequency ablation is necessary in the subset of patients with implantable cardioverter/defibrillator that have frequent or intractable ventricular arrhythmias. An emerging new therapy in the heart failure population is cardiac resynchronization therapy, which coordinates right and left ventricular pacing in a subset of patients with interventricular conduction delay.
Several randomized clinical trials have demonstrated improvements in heart failure-related symptoms, exercise tolerance, and reversal of ventricular remodeling. Meta-analysis of these trials has also demonstrated mortality benefit. Patient selection, left ventricular pacing site, and optimal device programming are issues that need further investigation. Recent trials have also studied the compatibility between cardiac resynchronization therapy and implantable cardioverter/defibrillator as a single device. Finally, the DAVID trial has raised concerns of conventional right ventricular pacing and the risk of heart failure in a subset of patients.
在美国，心力衰竭的患病率正呈流行趋势，并伴有显著的发病率和死亡率。很大一部分死亡是心源性猝死（SCD）所致。临床试验已证明，与抗心律失常药物相比，植入式心脏复律除颤器（ICD）在二级预防心源性猝死方面具有优越性。
最近，针对缺血性和非缺血性心力衰竭患者的心源性猝死一级预防开展了多项临床试验。2002年植入式心脏复律除颤器植入指南也已发布。对于植入式心脏复律除颤器的患者中出现频发或顽固性室性心律失常的亚组，抗心律失常药物或射频消融等辅助治疗是必要的。心力衰竭人群中一种新兴的治疗方法是心脏再同步治疗，它能使部分存在心室传导延迟的患者的左右心室起搏同步。
多项随机临床试验已证明，心力衰竭相关症状、运动耐量得到改善，心室重塑得以逆转。对这些试验的荟萃分析也显示出死亡率降低的益处。患者选择、左心室起搏部位以及最佳设备程控这些问题仍需进一步研究。近期试验还研究了心脏再同步治疗与植入式心脏复律除颤器作为单一设备的兼容性。最后，DAVID试验引发了人们对常规右心室起搏以及部分患者心力衰竭风险的关注。
