Kerlan Jeffrey E, Sawhney Navinder S, Waggoner Alan D, Chawla Mohit K, Garhwal Sanjeev, Osborn Judy L, Faddis Mitchell N
Cardiovascular Division, Washington University School of Medicine, St. Louis, Missouri 63110, USA.
Heart Rhythm. 2006 Feb;3(2):148-54. doi: 10.1016/j.hrthm.2005.11.006.
Atrioventricular (AV) delay optimization can be an important determinant of the response to cardiac resynchronization therapy (CRT) in patients with medically refractory heart failure and a ventricular conduction delay.
The purpose of this study was to compare two Doppler echocardiographic methods of AV delay optimization after CRT.
Forty consecutive patients (age 59 +/- 12 years) with severe heart failure, New York Heart Association class 3.1 +/- 0.4, QRS duration 177 +/- 23 ms, and left ventricular ejection fraction 26% +/- 6% referred for CRT were studied using two-dimensional Doppler echocardiography. In each patient, the acute improvement in stroke volume with CRT in response to two methods of AV delay optimization was compared. In the first method, the AV delay that produced the largest increase in the aortic velocity time integral (VTI) derived from continuous-wave Doppler (aortic VTI method) was measured. In the second method, the AV delay that optimized the timing of mitral valve closure to occur simultaneously with the onset of left ventricular systole was calculated from pulsed Doppler mitral waveforms at a short and long AV delay interval (mitral inflow method).
The optimized AV delay determined by the aortic VTI method resulted in an increase in aortic VTI of 19% +/- 13% compared with an increase of 12% +/- 12% by the mitral inflow method (P <.001). The optimized AV delay by the aortic VTI method was significantly longer than the optimized AV delay calculated from the mitral inflow method (119 +/- 34 ms vs 95 +/- 24 ms, P <.001). There was no correlation in the AV delay determined by the two methods (r = 0.03).
AV delay optimization by Doppler echocardiography for patients with severe heart failure treated with a CRT device yields a greater systolic improvement when guided by the aortic VTI method compared with the mitral inflow method.
对于药物治疗效果不佳且存在心室传导延迟的心力衰竭患者，房室（AV）延迟优化可能是心脏再同步治疗（CRT）反应的重要决定因素。
本研究旨在比较CRT后两种多普勒超声心动图优化AV延迟的方法。
连续纳入40例重度心力衰竭患者（年龄59±12岁），纽约心脏协会心功能分级为3.1±0.4级，QRS时限177±23毫秒，左心室射血分数26%±6%，采用二维多普勒超声心动图对其进行CRT治疗研究。比较每位患者采用两种AV延迟优化方法时CRT导致的每搏量急性改善情况。第一种方法是测量通过连续波多普勒获得的主动脉速度时间积分（VTI）增加最大时的AV延迟（主动脉VTI法）。第二种方法是根据短AV延迟和长AV延迟间期的脉冲多普勒二尖瓣波形计算使二尖瓣关闭时间与左心室收缩开始同时发生的最佳AV延迟（二尖瓣流入法）。
主动脉VTI法确定的优化AV延迟使主动脉VTI增加了19%±13%，而二尖瓣流入法使主动脉VTI增加了12%±12%（P<0.001）。主动脉VTI法确定的优化AV延迟显著长于二尖瓣流入法计算出的优化AV延迟（119±34毫秒对95±24毫秒，P<0.001）。两种方法确定的AV延迟之间无相关性（r = 0.03）。
对于接受CRT装置治疗的重度心力衰竭患者，与二尖瓣流入法相比，采用主动脉VTI法进行多普勒超声心动图AV延迟优化可带来更大的收缩功能改善。
