起搏器治疗对左室功能尚好房室传导阻滞患者的心功能影响

Impact of Cardiac Pacemaker Implantation on Cardiac Function in Patients with Atrioventricular Block and Preserved Systolic Left Ventricular Function

目的:评价左室功能尚好的房室阻滞患者植入心脏起搏后心力衰竭和左室收缩功能,探讨起搏器术后对左室功能的影响及其预测因素。方法:对象为48例因房室传导阻滞(AVB)行永久起搏治疗的患者,对其手术前后12导联心电图、超声心动图、心功能NYHA分级进行随访评估。结果:48例患者均行右室心尖起搏,其中男性26例、女性22例,平均随访12±9月。术后随访期间,13例患者发展为充血性心力衰竭,NYHA分级较术前增高(1.64±0.7对2.27±0.8,P<0.001),左室射血分数(LVEF)明显较术前降低(60%±6%对51%±13%,P<0.001)。对LVEF≤40%(A组)和>40%(B组)的患者对比分析发现,A组较B组患者的起搏QRS时限为长(181±32ms对151±26ms,P<0.01),室间延迟也较长(44±29ms对27±18ms,p=0.02);起搏QRS时限=180ms时,其检测左室功能异常的敏感性为54%,特异性为93%。结论:左室储备功能正常的房室阻滞患者,起搏后LVEF明显下降,起搏QRS时限可用以预测起搏后左室功能障碍的发生与否。

Objective：To assess left ventricular systolic function and predictive factors for developing left ventricular dysfunction after cardiac pacemaker implantation in patients with atrioventricular block and preserved systolic left ventricular function. Methods：Totally forty eight patients underwent 12 leads electrocardiogram and echocardiography before and after pacemaker implantation, NYHA functional classification and pacemaker were routinely followed. Results： The ventricular lead was implanted in the apex in all forty eight patients. After a median follow-up of 12 ± 9 months, clinical signs of congestive heart failure developed in 13 patients, NYHA classification scores were higher than before implantation （1.64 ± 0.7 versus 2.27 ±0.8, P〈0. 001 ）, left ventricnlar ejection fraction （LVEF） decreased significantly （60% ± 6% versus 51 % ± 13%, P〈0. 001）. 14 patients with LVEF≤40% （group A） and 34 patients with LVEF≥40% （group B） were compared in paced QRS duration and inter-ventricular delay. The paced QRS and inter ventricular delay were significantly prolonged in group A than those in group B, 181 ± 32 ms versus 151 ± 26 ms （P〈0.01） and 44 ± 29 ms versus 27 ± 18 ms（P = 0.02）, respectively. While paced QRS ≥180ms had a sensitivity of 54% and a specificity of 93 % for detecting left ventricular dysfunction. Conclusion：LVEF could be decreased significantly after pacemaker implantation in patients with atrioventricular block and preserved left ventricular systolic function at baseline, and predicted by prolonged paced QRS duration.