QRS时限对心脏再同步治疗疗效的预测价值

目的探讨QRS时限（QRSd）对心脏再同步治疗（CRT）的预测价值。方法入选患者心功能Ⅲ～Ⅳ级（NYHA分级）、在心室射血分数≤0．35、超声心动图提示心室不同步患者行CRT治疗。植入术前、术后当天及术后6个月行心电图和超声心动图检查。以治疗6个月后左心室收缩末容积较术前减小的百分数（△LVESV％）≥15％作为治疗有效的标准，分析术前QRSd、术后QRSd及QRS时限缩短值（△QRSd=术前QRSd-术后QRSd）对CRT疗效的预测价值。结果（1）共入选40例患者，随访期间1例死亡，2例失访，余37例进入分析。其中，7例为窄QRS波（〈120ms），30例为宽QRS波（≥120ms）。窄QRS波的CRT的有效率较宽QRS波，但差异无统计学意义（28．57％vs66．67％，P=0．079）；（2）宽QRS波组中，治疗有效者与无效者比，术前的左心室容积、左心室射血分数、QRSd、男女比例、心律、室内阻滞情况及△QRSd均差异无统计学意义（P〉0．05）；（3）宽QRS波组中，治疗有效者术后QRSd缩短（151．0±23．2）ms vs（167．0±25．2）ms，P〈0．05]，而无效者无变化（166．0±19．0）msvs（168．0±42．1）ms，P〉0．05]。受试者工作特征（ROC）曲线显示术前QRSd和△QRSd均不能预测CRT的疗效（P〉0．05）；△QRSd与△LVESV％无相关性（P〉0．05）。结论窄QRS波的CRT疗效可能较宽QRS波差。虽然QRSd缩短仅见于CRT有效，但术前QRSd和△QRSd均不足以预测宽QRS波的CRT疗效。

Value of QRS duration in predicting response to cardiac resynchronization therapy in patients with end-stage heart failure

Objective To evaluate the predictive value of QRS duration (QRSd) for response to car diac resynchronization therapy (CRT) in patients with end-stage heart failure. Methods Patients with heart failure scheduled for implantation of a CRT device were studied. Selection criteria for CRT included moderate to severe heart failure (New York Heart Association classes Ⅲ to Ⅳ), left ventricular ejection fraction (LVEF) ≤0.35, and ventricular asynchrony detected by echo-cardiography. Before CRT implantation, QRSd and 2-dimensional echocardiographical valuables (LV volumes and LVEF) were measured. QRSd, LVEF and LV volumes were reassessed immediately after CRT implantation and at 6-month follow-up. CRT response was defined as decreasing >15% in LV end-systolic volume (LVESV). The value for QRS duration to predict re sponse to CRT was assessed. Results A total of 40 patients were enrolled in the study. During the follow-up, one died and 2 lost to follow-up. The rest stepped into the analysis, including 7 with wide QRSd (≥120 ms) and 7 with narrow QRSd (< 120 ms). After 6 months of CRT, there was a trend that the rate of response to CRT in narrow QRSd group was lower than that in wide QRSd group (28. 57% vs 66. 67 %,P =0. 079). In wide QRSd group, no significant differences were observed in baseline QRSd, LV volumes and LVEF between responders and non-responders (P>0. 05). The QRSd was shortened in responders(151. 00 ±23. 15) ms vs (167.00±25. 15) ms,P<0.05] and remained unchanged(166. 00 ± 18. 97) ms vs (168. 00 ±42. 11) ms,P > 0. 05] immediately after CRT in non-responders of wide QRSd group. However, Receiver Operating Characteristic (ROC) curve showed that both baseline QRSd and change of QRSd (AQRSd) could not predict response to CRT(P > 0. 05). No significant relationship was demonstrated between AQRSd and ALVESV % (ALVESV % was the percent decrease in LVESV after 6 months CRT) at 6-month follow-up (P >0. 05). Conclusion Patients with narrow QRSd might have lower rate of response to CRT than wide QRSd patients. In wide QRSd patients,although shortening of QRSd after CRT was observed only in responders,but individual response varied highly, not allowing adequate selection of responders.