不同起搏模式对病态窦房结综合征患者心功能长期影响的探讨

目的前瞻性观察不同起搏模式对心功能长期的影响并探讨可能机制。方法 185例病态窦房结综合征（SSS）患者均采用常规方法经锁骨下静脉途径成功置入永久双腔心脏起搏器,术后即刻程控起搏器,根据SAS软件的PROC程序产生一组随机序列分为AAI（92例）及DDD（93例）起搏组。采用心脏超声观察术前,术后1、2、5年左室舒张末容积（LVEDV）、左室收缩末容积（LVESV）及左室射血分数（LVEF）的变化,比较两种起搏模式对左心功能的影响;术后1、2及5年进行随访结合起搏器程控记录房颤发生并记录DDD起搏组右室起搏百分比（VP%）,探讨VP%与心功能变化及房颤发生的关系。结果 AAI起搏组术前,术后1、2、5年随访LVEDV,LVESV及LVEF比较差异无统计学意义（P〉0.05）,DDD起搏组术前、术后1、2、5年LVEDV差异无统计学意义（P〉0.05）,术后5年LVESV（60.33±13.28）ml较术后1、2年增加,差异有统计学意义（F=2.7388,P〈0.05）,术后5年LVEF（41.75±8.74）%较术前、术后1、2年明显降低,差异有统计学意义（F=33.4393,P〈0.05）;AAI组与DDD组房颤的发生差异有统计学意义（P〈0.05）。术后5年DDD组中〈50%VP%,组中出现房颤患者为3例,≥50%VP%组中出现房颤患者为15例,两组之间房颤的发生率差异有统计学意义（P〈0.05）。结论在DDD起搏模式下,高的VP%可对患者的左心功能造成损害并增加房颤的发生。对于不合并房室传导阻滞的SSS患者,AAI起搏较DDD起搏能使患者更受益。

Impacts of different pacing modes on heart function

Objective To investigate the long term effects of different pacing modes on cardiac function and its possible mechanisms.Methods A total of 185 cases of sick sinus syndrome（SSS）patients were implanted with permanent pacemaker and divided into the AAI（n=92）and the DDD（n=93）pacing mode groups.The Left ventricular end-diastolic volume（LVEDV）,Left ventricular end-systolic volume（LVESV）and Left ventricular ejection fraction（LVEF）were measured by echocardiography before and after implantation of pacemaker and the patients were follow-up for 5 years.Comparison of the impact of the two pacing modes on left ventricular function was analysed.Program-control of DDD pacemaker was carried out to observe Percentage of right ventricular pacing（VP%）after implantation and to find the relationship between VP% with heart function and the incidence of atrial fibrillation（AF）.Results There were no difference between the preoperative and the postoperative measurements on LVEDV,LVESV and LVEF in the AAI group.After 5-year follow-up in the DDD pacing group,LVESV（60.33±13.28）ml were increased（F=2.7388,P0.05）,but LVEF（41.75±8.74）% were declined（F=33.4393,P0.05）.There were difference between the AAI and the DDD pacing group on incidence of AF（1.08% vs 9.72%,P0.05）.In the DDD group after 5 years of follow up,3 out of 43 patients with VP%50% developed Af while 15 out of 50 patients with VP%≥50% developed Af（P0.05）.Conclusions The higher percentage of right revtricular pacing can damage left ventricular function and increase the rate of atrial fibrillation in DDD pacing.The SSS patients without AVB may benefit more from AAI pacing.