优化左房室传导时间对植入双腔起搏器的三度房室传导阻滞患者血流动力学及预后的影响

Effect of optimizing left atrioventricular interval on the hemodynamics and clinical prognosis of patients with atrioventricular block after dual-chamber pacemaker implantation.

目的探讨优化左房室传导时间(LAVI)对三度房室传导阻滞植入双腔起搏器患者血流动力学及预后的影响。方法对120例三度房室传导阻滞植入双腔起搏器患者,随机分为LAVI优化组和非优化组。于起搏器植入术后3个月(观察基点)行食管心电图检查,测量两组患者的房间传导时间(IACT)、室间传导时间(IVCT)并计算在起搏器出厂默认的房室延迟(AVD)状态下的LAVI,其中优化组随即进一步在超声心动图指导下,调整起搏器的AVD以取得左房室最佳机械同步状态下的最优LAVI。所有患者于术后观察基点,6、12、18个月接受超声心动图检查,并观察心电传导参数、相关临床表现及预后指标,分析最优LAVI与心率的关系。结果(1)优化组平均最优LAVI为(130.8±11.9)ms,较默认的LAVI(起搏状态下)值(120.7±18.7 ms)延长(P<0.05)。(2)优化组最优LAVI与心率呈负相关(r=-0.955,P<0.05),心率<70次/分,最优LAVI为140 ms;心率70~80次/分,最优LAVI为130 ms;心率>80次/分,最优LAVI为120 ms。(3)优化LAVI可使优化组E峰减速时间(EDT)、等容舒张时间(IVRT)即刻改善(P<0.05)。(4)优化组患者的左室射血分数(LVEF)、EDT、IVRT于术后6个月开始优于非优化组(P<0.05),左房容积指数、E/e′(二尖瓣口舒张早期血流速度与二尖瓣环舒张早期运动速度的比值)于术后12个月开始优于非优化组(P<0.05)。(5)非优化组的LVEF、EDT在术后18个月的随访期内逐步降低(P均<0.05);而IVRT、左房容积指数则在整个随访期内逐步增加(P均<0.05)。优化组的E/e′在随访期内逐步增加(P<0.05),EDT则在随访期内逐步降低(P<0.05)。(6)随访至终点,优化组累计新发阵发性心房颤动的发生率明显低于非优化组(8.3%vs 23.3%,P<0.05)。结论优化LAVI可以改善三度房室传导阻滞植入双腔起搏器患者的血流动力学,并减少心房颤动的发生。

Objective To investigate the effect of optimized left atrioventricular interval(LAVI)on the hemodynamics and clinical prognosis of patients with third-degree atrioventricular block(AVB)after double-chamber pacemaker implantation.Methods One hundred and twenty patients with third-degree AVB after double-chamber pacemaker implantation were randomly divided into two groups,LAVI optimized group and non-optimized group.All patients accepted esophageal electrocardiogram tests at three months after the implantation,to exam the interatrial conduction time(IACT)of sinus rhythm and pacing rhythm,and interventricular conduction time(IVCT),and calculate the default LAVI under the default state of atrioventricular delay(AVD).Patients in LAVI optimized group were adjusted the AVD to the optimal left atrioventricular mechanical synchronization guiding by echocardiography,obtained the optimal LAVI.All patients received echocardiography at 6,12,and 18months after the implantation,recorded the pacemaker parameters,clinical manifestations and prognostic indicators.Then the correlation between optimal LAVI and heart rate was analyzed.Results(1)In the optimal group,the average optimal LAVI was(130.83±11.92)ms,longer than the default pacing LAVI(120.7±18.7)ms(P<0.05).(2)In the optimization group,the optimal LAVI was negatively correlated with heart rate(r=-0.955,P<0.05).Then the optimal LAVI was 140ms when the heart rate was under 70beats/min.When the heart rate was between 70and 80beats/min,the optimal LAVI was 130ms.And when the heart rate was above 80beats/min,the optimal LAVI was 120ms.(3)Optimizing LAVI could immediately improve the E-peak deceleration time(EDT)and isovolumic relaxation time(IVRT)in the optimized group(P<0.05).(4)The left ventricular ejection fraction(LVEF),EDT and IVRT in the optimized group were better than those in the non-optimized group 6months after the implantation(P<0.05).And the left atrial volume index and E/e′were better than those in the non-optimized group 12months after the implantation.(5)The LVEF and EDT in the non-optimized group were gradually decreased during the 18-month follow-up(all P<0.05).IVRT and the left atrial volume index increased gradually throughout the follow-up period(P<0.05),while the EDT decreased in the same time.(6)At the end of the follow-up period,the incidence of atrial fibrillation in the optimized group was significantly lower than that in the non-optimized group(8.3%vs 23.3%,P<0.05).Conclusion Optimized LAVI can improve cardiac hemodynamics,and reduce the incidence of atrial fibrillation in patients with third-degree AVB after dual-chamber pacemaker implantation.