Department of Cardiovascular Medicine, Heart and Vascular Institute, Cleveland Clinic, Cleveland, Ohio 44195, USA.
J Am Coll Cardiol. 2012 Aug 14;60(7):592-8. doi: 10.1016/j.jacc.2012.03.059. Epub 2012 Jul 11.
The goal of this study was to examine the relative impact of QRS morphology and duration in echocardiographic responses to cardiac resynchronization therapy (CRT) and clinical outcomes.
At least one-third of all patients treated with CRT fail to derive benefit. Patients without left bundle branch block (LBBB) or patients with smaller QRS duration (QRSd) respond less or not at all to CRT.
We retrospectively assessed baseline characteristics, clinical and echocardiographic response, and outcomes of all patients who received CRT at our institution between December 2003 and July 2007. Patients were stratified into 4 groups according to their baseline QRS morphology and QRSd.
A total of 496 patients were included in the study; 216 (43.5%) had LBBB and a QRSd ≥150 ms, 85 (17.1%) had LBBB and QRSd <150 ms, 92 (18.5%) had non-LBBB and a QRSd ≥150 ms, and 103 (20.8%) had non-LBBB and QRSd <150 ms. Echocardiographic response (change in ejection fraction) was better in patients with LBBB and QRSd ≥150 ms (12 ± 12%) than in those with LBBB and QRSd <150 ms (8 ± 10%), non-LBBB and QRSd ≥150 ms (5 ± 9%), and non-LBBB and QRSd <150 ms (3 ± 11%) (p < 0.0001). In a multivariate stepwise model with change in ejection fraction as the dependent variable, the presented classification was the most important independent variable (p = 0.0003). Long-term survival was better in LBBB patients with QRSd ≥150 ms (p = 0.02), but this difference was not significant after adjustment for other baseline characteristics (p = 0.15).
QRS morphology is a more important baseline electrocardiographic determinant of CRT response than QRSd.
本研究旨在探讨心电图 QRS 形态和持续时间对心脏再同步治疗（CRT）反应和临床结局的相对影响。
接受 CRT 治疗的患者中至少有三分之一未能从中获益。无左束支传导阻滞（LBBB）或 QRS 持续时间（QRSd）较小的患者对 CRT 的反应较小或无反应。
我们回顾性评估了 2003 年 12 月至 2007 年 7 月期间在我院接受 CRT 的所有患者的基线特征、临床和心电图反应以及结局。根据患者的基线 QRS 形态和 QRSd 将患者分为 4 组。
共有 496 例患者纳入研究；216 例（43.5%）有 LBBB 和 QRSd≥150ms，85 例（17.1%）有 LBBB 和 QRSd<150ms，92 例（18.5%）有非 LBBB 和 QRSd≥150ms，103 例（20.8%）有非 LBBB 和 QRSd<150ms。心电图反应（射血分数变化）在 LBBB 和 QRSd≥150ms 的患者中较好（12±12%），明显优于 LBBB 和 QRSd<150ms 的患者（8±10%）、非 LBBB 和 QRSd≥150ms 的患者（5±9%）和非 LBBB 和 QRSd<150ms 的患者（3±11%）（p<0.0001）。在以射血分数变化为因变量的多变量逐步模型中，所提出的分类是最重要的独立变量（p=0.0003）。QRSd≥150ms 的 LBBB 患者长期生存率更好（p=0.02），但在调整其他基线特征后，这种差异无统计学意义（p=0.15）。
QRS 形态是 CRT 反应的比 QRSd 更重要的基线心电图决定因素。
