【摘要】 目的:探讨术前自身QRS波时限(intrinsic QRS duration,IQRSd)对右心室心尖部(right ventricular apex,RVA)起搏患者心功能下降的预测作用。方法:选取因三度房室传导阻滞(Ⅲ°AVB)植入双腔全自动型起搏器(DDD)或单腔同步型起搏器(VVI)患者42例。其中,末次随访时左室射血分数较术前下降的绝对值(ΔLVEF)≥5%的患者22例(ΔLVEF≥5%组,DDD 12例,VVI 10例),同期ΔLVEF<5%患者20例(ΔLVEF<5%组,DDD 11例,VVI 9例),两组比较,研究起搏引起心功能下降的可能原因和可能的预测因子。每例患者在起搏器植入术前行12导联心电图和超声心动图检查,术后随访时记录起搏心电图、超声心动图及右心室累积起搏比例。结果:两组患者平均随访77.3个月,ΔLVEF≥5%组左室射血分数(left ventricular ejection fraction,LVEF)由术前(64.20±6.30)%降至(40.60±10.00)%(P<0.001),左房内径(left atrial diameter,LAD)由术前(34.77±6.42)mm增大至(41.00±7.45)mm(P<0.001),左室舒张末期内径(left ventricular end-diastolic dimension,LVEDD)由术前(49.82±4.86)mm明显增大至(55.59±8.44)mm(P<0.001),差异均有统计学意义;ΔLVEF<5%组LVEF由术前(65.40±3.25)%降低至(64.94±3.00)%(P=0.543),LAD由术前(37.40±4.84)mm增加至(38.15±5.83)mm(P=0.347),LVEDD由术前(48.30±3.95)mm增加至(49.00±3.87)mm(P=0.090),变化均无统计学意义;四格表卡方检验提示植入起搏器后术前IQRSd≥110 ms组较术前IQRSd<110 ms组患者发生心功能下降比率更高(P=0.002);Kaplan-Meier分析发现植入起博器后术前IQRSd≥110ms患者较术前IQRSd<110 ms患者心功能下降发生时间更早。COX回归分析显示,术前IQRSd≥110 ms是左室收缩功能下降的独立预测危险因素(P<0.05)。结论:RVA长期起搏可引起心脏结构改变和左室收缩功能下降;术前IQRSd≥110 ms患者左室收缩功能下降发生率高且时间更早,术前IQRSd≥110 ms是起搏依赖患者左室收缩功能下降的独立预测危险因子。更多还原

【Abstract】 Objective:To investigate the predictive value of intrinsic QRS duration(IQRSd) for left ventricular function deterioration in patients dependent on right ventricular apical(RVA) pacing.Methods:In this study,42 patients with third degree atrioventricular block who underwent pacemaker implantation were included.Twenty-two patients with absolute reduction value of left ventricular ejection fraction(ΔLVEF)≥5% after pacing(group with ΔLVEF≥5%) and 20 patients with ΔLVEF<5% after pacing(group with ΔLVEF<5%) were enrolled to investigate the possible reasons or predictors for the cardiac function deterioration.The examination results of 12-lead electrocardiography and echocardiography,and clinical conditions were recorded for every patient before the implantation and during the follow-up.The cumulative pacing rate of pateints were also obtained at each follow-up visit.Results:After 77.3 months of follow-up,left ventricular ejection fraction(LVEF) decreased significantly from(64.20 ± 6.30)% to(40.60 ± 10.00)%(P < 0.001) while left atrial diameter(LAD) and left ventricular end-diastolic dimension(LVEDD) enlarged significantly in group with ΔLVEF≥5%[LAD:(34.77 ± 6.42)mm vs.(41.00 ± 7.45)mm;LVEDD:(49.82 ± 4.86)mm vs.(55.59 ± 8.44)mm;P < 0.001)].However,the average LVEF,LAD and LVEDD levels in group with ΔLVEF<5% after pacing were not statistically different from those before pacing[LVEF:(65.40 ± 3.25)% vs.(64.94 ± 3.00)%;LAD:(37.40 ± 4.84)mm vs.(38.15 ± 5.83)mm;LVEDD:(48.30 ± 3.95)mm vs.(49.00 ± 3.87)mm].Kaplan-Meier analysis revealed that LVEF diminution after pacing appeared significantly earlier in patients with IQRSd≥110 ms than that in patients with IQRS<110 ms.Chi Square Test showed the rate of LVEF diminution was significantly higher in patients with IQRSd≥110 ms than that in patients with IQRSd<110 ms(P < 0.05).COX regression analysis indicated that IQRSd≥110 ms was the independent predictor of left ventricular systolic function decrease(P < 0.05).Conclusion:Long-term RVA pacing leads to deterioration of left ventricular systolic function and cardiac remodeling.In patients with IQRSd≥110 ms,deterioration of left ventricular systolic function occured earlier and more serious than in those with IQRSd<110 ms.IQRSd≥110 ms is the independent predictor of LVEF reduction in patients dependent on right ventricular pacing.更多还原