QRS时限对左心室导线电延迟与心脏再同步治疗长期疗效相关性的影响

Impact of QRS duration on the relationship between left ventricle lead electrical delay and clinical response after cardiac resynchronization therapy

目的 探讨QRS时限是否影响左心室导线电延迟（LVLED）与心脏再同步治疗（CRT）长期疗效的相关性.方法 前瞻性入选2011年10月至2013年3月在阜外心血管病医院成功植入CRT患者,在围术期测量Q波起始到左心室导线感知波最高峰的时间间距（QLV）反映LVLED.根据患者基线QRS时限分为宽QRS组（≥150 ms）和窄QRS组（＜150 ms）,基线及术后定期检查超声心动图及随访情况.CRT有反应定义为术后最后1次随访时左心室射血分数提高≥0.05.结果 共入选93例患者,81例患者完成（15±3）个月的随访.平均年龄（60.1±10.4）岁,72％为左束支阻滞,80％为非缺血性心肌病,37.0％为女性.宽QRS组61例,窄QRS组20例.宽QRS组的QLV显著长于窄QRS组[（109.9±38.1） ms对（77.5±37.6） ms,P＜0.05].整体CRT有反应率为66.7％.宽QRS组CRT有反应率显著高于窄QRS组（72.1％对50％,P＜0.05）.在宽QRS组,CRT有反应率随QLV四分位分组显著增加（57.0％,73.3％,80.0％,87.5％,P=0.017）.但窄QRS组QLV四分位组间CRT有反应率差异无统计学意义（P＞0.05）.多因素回归分析校正年龄、性别、束支阻滞和缺血性心肌病后,宽QRS组长QLV与CRT有反应显著相关（OR4.12,95％ CI 2.17～8.68,P=0.012）.但窄QRS组QLV与CRT反应无相关性（P＞0.05）.结论 只有当基线QRS时限≥150 ms时,应用LVLED指导左心室导线位置有助于提高CRT的长期疗效.

Objective The left ventricle lead electrical delay （LVLED）has been associated with reverse remodeling after cardiac resynchronization therapy（CRT）.The impact of QRS duration on the relationship between LVLED and CRT clinical response remains unclear.Methods We prospectively enrolled a series of consecutive patients undergoing CRT implantation according to standard clinical indications.The LVLED was measured from the onset of the surface electrco cardiogram QRS complex to the first large peak of the unipolar LV tip to can intracardiac electrogram during spontaneous rhythm via the programmer,which is also called QLV.Patients were devided into with wide or with narrow QRS groups according to the QRS duration（≥or〈150 ms）.Echocardiograms were assessed at baseline and follow-up interviews after CRT implantation.CRT response was defined as an absolute improvement in LV ejection fraction of ≥5 percentage points after CRT.Results A total of 93 patients entered into this study,and 81 patients [mean age（60.1 ± 10.4）years,72% of the patients had left bundle-branch block morphology,80% of the patients had non-ischemia cardiomyopathy,37.5% female,mean QRS interval （165.1 ± 22.5 ms）] finished a mean follow-up of （15 ±3） months.Patients with wide QRS had longer QLV intervals [（109.9±38.1） ms vs.（77.5±37.6） ms,P〈0.05] and more CRT responders（70.8% vs.50%,P〈0.05） than patients with narrow QRS （total of 66.7% responders of CRT）.In patients with wide QRS,CRT responders increased progressively from 50.0% to 88.4% when separated by quartiles based on QLV interval（P 〈0.05）.However,no relationship was found between QLV intervals and CRT response（P〉0.05） in patients with narrow QRS.After adjustment for age,sex,bundle-branch block,and ischemia cardiomyopathy by multivariate logistic regression analysis,the relationship between QLV intervals and CRT response was still significant in patients with wide QRS （OR：4.12,95% CI：2.17 to 8.68,P =0.012）,but not in patients with narrow QRS （P〉 0.05）.Conclusions LVLED is strongly associated with improvement in LV ejection fraction after CRT only in patients with QRS ≥ 150 ms,but not in patients with QRS〈 150 ms.Impact of QRS duration should be considered when LVLED is used to predict CRT clinical response.