左心室起搏阈值管理功能在心脏再同步治疗中的初步临床应用体会

Clinical application of Concerto cardiac resynchronization therapy defibrillator in patients with severe heart failure

目的目前在国内使用的心脏再同步治疗（CRT）起搏器及心脏再同步治疗除颤器（CRT-D）中，仅美敦力公司的Concerto具有左心室起搏阈值管理（LVCM）功能。本文初步探索植入Concerto患者，LVCM功能的准确性及临床意义。方法5例药物治疗无效的严重心力衰竭患者植入了Concerto型CRT—D，术后打开LVCM功能，起搏器自动记录每天起搏阈值变化情况，并在每一个随访时间点收集LVCM自动测算的左心室起搏阈值并与人工测算值进行对比。结果所有患者术后在满足测试条件后自动开启LVCM功能，并在事先设置的时间点自动测试起搏阈值，根据阈值自动调整输出；术后1～2个月起搏阚值波动较大。LVCM测算的左心室起搏阈值与手动测算值完全符合率为83．3％（20／24），如果按差值0．5V计算，二者符合率为96．8％（23／24）。结论LVCM功能与手工测试具有很高的符合率；使用此功能能最大限度地保证左心室或双心室有效同步起搏，对提高CRT术后疗效具有重要临床意义。

Objective Medtronic Concerto cardiac resynchronization therapy defibrillator （CRT-D） is the only one device used in China's Mainland with left ventricular capture management （LVCM） algorithm. Our aim was to assess the clinical application and accuracy of LVCM in patients with Concerto CRT-D implantation. Methods Concerto CRT-D systems were implanted into 5 patients with drug-resistant heart failure. Daily fluctuation of LV thresholds acquired by the LVCM algorithm up to 6-month-follow-up. LV threshold measurements by LVCM were compared with manual LV threshold tests at periodic visits. Results All high threshold detections and all automatic modulation of LV pacing output were adjusted appropriately, LV threshold fluctuated markedly in first 2 months. LVCM tests were identical to manual LV threshold tests in 20 out of 24 attempts（83.3% ）. The proportion of LVCM threshold tests within one programming step of the manual threshold test was 96. 8% （23/24）. Conclusion This study demonstrated that LVCM algorithm is accurate, reliable, and clinically equivalent to the manual LV threshold test. LVCM could uhimately result in complete LV capture and improve clinical effects of CRT.