Institute of Vascular Medicine and Division of Cardiology, Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong, People's Republic of China.
J Cardiovasc Electrophysiol. 2012 Apr;23(4):384-90. doi: 10.1111/j.1540-8167.2011.02210.x. Epub 2011 Nov 7.
Right atrial (RA) appendage pacing may prolong atrial conduction time (ACT). This study aimed to investigate if RA appendage pacing can induce intra- and interatrial dyssynchrony and if atrial dysfunction and dyssynchrony can predict atrial high rate episodes (AHREs) in the first year after pacing.
Patients implanted with dual-chamber pacemakers for symptomatic bradycardia were enrolled. Cumulative percentage of RA appendage pacing (Cum%AP) during 1-year follow-up and AHREs were recorded. Full Doppler echocardiography studies were performed before implantation and 1 year after pacing. ACT and peak atrial velocities (Sm-la, Em-la, Am-la) were measured. One hundred ten patients (age 70.5 ± 11 years; 53 males) were recruited and completed 1-year follow-up. ACT of both RA and left atrial (LA) were more prolonged in patients with Cum%AP > 75% than those with <25%. Intra- and interatrial dyssynchrony was more obvious in patients with Cum%AP > 75% (22.3 ± 12.2 milliseconds vs 9.5 ± 6.2 milliseconds; 53.9 ± 29.7 milliseconds vs 19.7 ± 17.3 milliseconds; both P < 0.001). AHREs occurred in 29% of patients. Atrial pump function and interatrial dyssynchrony independently predicted AHREs in multivariate analysis. Receiver operating characteristic curve provided a cutoff value of Am-la <5.3 cm/s, which predicted AHREs with a sensitivity of 71% and a specificity of 75% (area under the curve, 0.822; P < 0.001).
RA appendage pacing causes atrial conduction delay with intra- and interatrial dyssynchrony. Atrial dysfunction and interatrial dyssynchrony are related to AHREs in the first year after pacing.
右心耳（RA）起搏可能会延长心房传导时间（ACT）。本研究旨在探讨 RA 心耳起搏是否会引起房内和房间隔不同步，以及心房功能障碍和不同步是否可以预测起搏后第一年的心房高频事件（AHREs）。
入选因症状性心动过缓植入双腔起搏器的患者。记录 1 年随访期间的 RA 心耳起搏累计百分比（Cum%AP）和 AHREs。在植入前和起搏后 1 年进行全多普勒超声心动图研究。测量 ACT 和峰值心房速度（Sm-la、Em-la、Am-la）。共纳入 110 例患者（年龄 70.5±11 岁；53 名男性），并完成了 1 年随访。Cum%AP＞75%的患者的右心房（RA）和左心房（LA）的 ACT 均比 Cum%AP＜25%的患者更长。Cum%AP＞75%的患者的房内和房间隔不同步更为明显（22.3±12.2 毫秒比 9.5±6.2 毫秒；53.9±29.7 毫秒比 19.7±17.3 毫秒；均 P＜0.001）。29%的患者发生了 AHREs。多元分析显示，心房泵功能和房间隔不同步独立预测 AHREs。受试者工作特征曲线提供了 Am-la＜5.3cm/s 的截断值，其预测 AHREs 的敏感性为 71%，特异性为 75%（曲线下面积为 0.822；P＜0.001）。
RA 心耳起搏导致心房传导延迟，伴有房内和房间隔不同步。起搏后第一年，心房功能障碍和房间隔不同步与 AHREs 相关。
