定量组织速度成像评价不同房室间期对双腔起搏左室收缩功能影响的研究

Quantitative Tissue Velocity Imaging for Evaluating the Effects of Different Atrioventricular Delay on the Left Ventricular Systolic Function in Patients with Dual-chamber Pacing

目的 应用定量组织速度成像 (QTVI)评价不同房室 (AV)间期对DDD双腔起搏患者的左室收缩功能的影响以探求最佳AV间期。方法 3 0例植入DDD双腔起搏器的患者 ,在DDD起搏方式下将AV间期程控为 10 0ms、13 0ms、15 0ms、170ms、2 0 0ms ,测定后间隔、侧壁、前壁、下壁、前间隔和后壁六个部位二尖瓣环的收缩期平均峰值速度(Vs)及从QTVI曲线上A波结束到S波开始的时间 (TA -S) ,并将Vs与二维法所测的心输出量 (CO )作相关分析。结果 QTVI所测定的二尖瓣环的Vs与CO呈正相关 (r =0 .62 ,P <0 .0 1)。不同的AV间期明显影响Vs的值 ,TA -S则随AV间期的延长而增大。以Vs为标准 ,DDD起搏方式下最佳AV间期为 ( 15 4± 2 4)ms ,相应的TA -S 的平均值为 ( 7.6±2 .3 )s- 2 。结论 DDD双腔起搏时房室 (AV)间期影响左室收缩功能。QTVI可用于选择DDD双腔起搏的最佳AV间期。

Objective To examine the effects of variations in atrioventricular delay (AVD) on the left ventricular systolic function by quantitative tissue velocity imaging (QTVI) and determine the optimal AVD in patients with Dual-chamber Pacing. Methods Thirty patients with Dual-chamber Pacemakers were studied. DDD pacing mode was programmed according to five different AVD: 100 ms, 130 ms, 150 ms,170 ms and 200 ms. The peak systolic mean velocity (Vs) and the time between A wave and S wave of the profiles achieved by QTVI(T A-S )were measured at six mitral annular segments from 2-dimensional echocardiograms, and Vs were compared with cardiac output(Co). Results There was a significant correlation between the mean Vs and Co in the patients with Dual-chamber Pacing (r=0.62, P<0.001). In patients with Dual-chamber Pacing, different AVD affected Vs significantly, while T A-S increased with AVD prolonged. According to Vs individually, the optimal AVD was 154±24 ms such that the mean T A-S was 7.6 ±2.3 s-2 . Conclusion In patients with Dual-chamber Pacing, different AVD affected the left ventricular systolic function. Measuring the peak systolic mean velocity by QTVI is helpful to determine the optimal AVD in individual patients.