起搏部位选择
传统上,右心室起搏通常是从心尖开始,这个部位容易操作而且导联可固定良好。 但是,人们逐渐认识到该起搏部位不总能达到最佳的血液动力学结果。[14]European Society of Cardiology (ESC) Task Force on cardiac pacing and resynchronization therapy; European Heart Rhythm Association (EHRA). 2013 ESC Guidelines on cardiac pacing and cardiac resynchronization therapy. Eur Heart J. 2013 Aug;34(29):2281-329.http://eurheartj.oxfordjournals.org/content/34/29/2281.longhttp://www.ncbi.nlm.nih.gov/pubmed/23801822?tool=bestpractice.com 其他起搏部位,比如,右室流出道、室间隔、希氏束、希氏束旁部位和通过冠状窦的左心室起搏[28]Victor F, Mabo P, Mansour H, et al. A randomized comparison of permanent septal versus apical right ventricular pacing: short term results. J Cardiovasc Electrophysiol. 2006;17:238-242.http://www.ncbi.nlm.nih.gov/pubmed/16643392?tool=bestpractice.com[29]Victor F, Leclercq C, Mabo P, et al. Optimal right ventricular pacing site in chronically implanted patients: a prospective randomized crossover comparison of apical and outflow tract pacing. J Am Coll Cardiol. 1999;33:311-316.http://www.ncbi.nlm.nih.gov/pubmed/9973008?tool=bestpractice.com[30]Tse HF, Yu C, Wong KK, et al. Functional abnormalities in patients with permanent right ventricular pacing:the effect of sites of electrical stimulation. J Am Coll Cardiol. 2002;40:1451-1458.http://www.ncbi.nlm.nih.gov/pubmed/12392836?tool=bestpractice.com[31]Occhetta E, Bortnik M, Magnani A, et al. Prevention of ventricular desynchronization by permanent para-Hisian pacing after atrioventricular node ablation in chronic atrial fibrillation: a crossover, blinded, randomized study versus apical right ventricular pacing. J Am Coll Cardiol. 2006;47:1938-1945.http://www.ncbi.nlm.nih.gov/pubmed/16697308?tool=bestpractice.com 已经过研究,看起来是安全的,有希望获得更好的血液动力学结果。 但是,Protect Pace研究,一项进行两年以上的随机对照试验中,将患者分为右室心尖起搏组和右室室间隔组,结果并不支持室间隔组在保护左心室功能方面的优越性。[32]Kaye GC, Linker NJ, Marwick TH, et al; Protect-Pace trial investigators. Effect of right ventricular pacing lead site on left ventricular function in patients with high-grade atrioventricular block: results of the Protect-Pace study. Eur Heart J. 2015;36:856-862.http://eurheartj.oxfordjournals.org/content/36/14/856.longhttp://www.ncbi.nlm.nih.gov/pubmed/25189602?tool=bestpractice.com
生物起搏器
病毒载体,人胚胎干细胞和成人骨髓间充质细胞已被用来提供生物起搏。[33]Plotnikov AN, Shlapakova I, Szabolcs MJ, et al. Xenografted adult human mesenchymal stem cells provide a platform for sustained biological pacemaker function in canine heart. Circulation. 2007;116:706-713.http://circ.ahajournals.org/content/116/7/706.fullhttp://www.ncbi.nlm.nih.gov/pubmed/17646577?tool=bestpractice.com 该治疗已经进行了充分的试验,但仅在动物中进行,在未来有希望用于人类。
无线起搏器
起搏器导线植入失败及相关并发症一直是比较严重的临床难题。 取出故障导线相关并发症很严重,在少数病例中,甚至可能是致命的。 因此,无线器械技术十分诱人。 使用自动产能系统[34]Goto H, Sugiura T, Harada Y, et al. Feasibility of using the automatic generating system for quartz watches as a leadless pacemaker power source. Med Biol Eng Comput. 1999;37:377-380.http://www.ncbi.nlm.nih.gov/pubmed/10505390?tool=bestpractice.com 和超声作为能量来源,[35]Lee KL, Tse HF, Echt DS, et al. Temporary leadless pacing in heart failure patients with ultrasound-mediated stimulation energy and effects on the acoustic window. Heart Rhythm. 2009;6:742-748.http://www.ncbi.nlm.nih.gov/pubmed/19427274?tool=bestpractice.com[36]Lee KL, Lau CP, Tse HF, et al. First human demonstration of cardiac stimulation with transcutaneous ultrasound energy delivery: implications for wireless pacing with implantable devices. J Am Coll Cardiol. 2007;50:877-883.http://www.ncbi.nlm.nih.gov/pubmed/17719475?tool=bestpractice.com[37]Echt DS, Cowan MW, Riley RE, et al. Feasibility and safety of a novel technology for pacing without leads. Heart Rhythm. 2006;3:1202-1206.http://www.ncbi.nlm.nih.gov/pubmed/17018352?tool=bestpractice.com 目前正在动物和人类中对此进行研究。这仍主要处于试验阶段。欧洲和美国率先开展此类器械的人体植入。在一项多中心研究中,526 例患者中有 504 例成功植入无线起搏器。[38]Reddy VY, Exner DV, Cantillon DJ, et al.; LEADLESS II Study Investigators. Percutaneous implantation of an entirely intracardiac leadless pacemaker. N Engl J Med. 2015;373:1125-1135.http://www.nejm.org/doi/full/10.1056/NEJMoa1507192#t=articlehttp://www.ncbi.nlm.nih.gov/pubmed/26321198?tool=bestpractice.com 这些起搏器符合大多数患者的预定起搏和感知要求,15 例患者中约有 1 例发生与器械相关的严重不良事件。