García-Seara Javier, Iglesias Alvarez Diego, Alvarez Alvarez Belen, Gude Sampedro Francisco, Martínez Sande Jose L, Rodríguez-Mañero Moisés, Kreidieh Bahij, Fernández-López Xesus Alberte, González Melchor Laila, González Juanatey José Ramón
Cardiology Department, Arrhythmia Unit, Clinical University Hospital of Santiago de Compostela, CIBER CV Spain, Travesía Choupana s/n, 15701, Santiago de Compostela, Spain.
Cardiology Department, Clinical University Hospital of Santiago de Compostela, CIBER CV Spain, Travesía Choupana s/n, 15701, Santiago de Compostela, Spain.
J Interv Card Electrophysiol. 2018 Jun;52(1):91-101. doi: 10.1007/s10840-018-0363-x. Epub 2018 Apr 3.
Left bundle branch block (LBBB) configuration has been described as a predictor of response to cardiac resynchronization therapy (CRT). We investigated whether different subtypes of true LBBB configuration could help select patients with better response and clinical outcome.
This retrospective study included 198 consecutive LBBB patients implanted with a CRT. True LBBB was defined using the Strauss and the Predict study criteria. Echocardiographic response was evaluated by the reduction in left ventricular end-systolic volume (LVESV) and the increase in left ventricular ejection fraction (LVEF). Clinical response was defined as an improvement in one category of the NYHA functional class.
Patients with true LBBB had a greater improvement in both LVESV reduction (median = - 27.6%, interquartile range = [- 4.9, - 50.1]) and LVEF increase (median 10.8 ± 10) than those with non-true LBBB (- 19.7%, [16.7, - 48.0]) p = 0.04 and 5.1 ± 10, p = 0.03, respectively. No differences were exhibited between true LBBB Strauss group (- 26.7%, [- 11.0, - 46.9]) and true LBBB Predict group (- 26.6%, [- 15.9, - 39.4]). There were no statistically significant differences in the percentage of patients with clinical response, assessed by NYHA improvement, among all groups. In the Cox model for death, age, ischemic etiology, and ΔLVESV were independent predictors of mortality. True LBBB (Strauss + Predict) patients had a trend towards lower mortality than non-true LBBB [HR = 0.55, 95% CI = (0.22-1.15)], p = 0.08. In the Cox model for HF hospitalization, age, sex male, prior LVEF, and ΔLVESV were independent predictors. True LBBB (Strauss + Predict) patients had a significantly lower risk of developing HF hospitalization than those with non-true LBBB [0.45 (0.21-0.90)], p = 0.029.
Patients with true LBBB, either Strauss or Predict criteria, had greater echocardiographic response and lower incidence of HF hospitalization than non-true LBBB when implanted with CRT.
左束支传导阻滞（LBBB）形态已被描述为心脏再同步治疗（CRT）反应的预测指标。我们研究了不同亚型的真性LBBB形态是否有助于选择反应更好和临床结局更佳的患者。
这项回顾性研究纳入了198例连续植入CRT的LBBB患者。采用施特劳斯和Predict研究标准定义真性LBBB。通过左心室收缩末期容积（LVESV）的减少和左心室射血分数（LVEF）的增加来评估超声心动图反应。临床反应定义为纽约心脏协会（NYHA）心功能分级中一类的改善。
真性LBBB患者在LVESV减少（中位数=-27.6%，四分位间距=[-4.9，-50.1]）和LVEF增加（中位数10.8±10）方面的改善均大于非真性LBBB患者（分别为-19.7%，[16.7，-48.0]，p=0.04和5.1±10，p=0.03）。真性LBBB施特劳斯组（-26.7%，[-11.0，-46.9]）和真性LBBB Predict组（-26.6%，[-15.9，-39.4]）之间未表现出差异。在所有组中，通过NYHA改善评估的临床反应患者百分比无统计学显著差异。在死亡的Cox模型中，年龄、缺血性病因和ΔLVESV是死亡率的独立预测因素。真性LBBB（施特劳斯+Predict）患者的死亡率有低于非真性LBBB患者的趋势[风险比（HR）=0.55，95%置信区间（CI）=（0.22-1.15）]，p=0.08。在心力衰竭住院的Cox模型中，年龄、男性性别、既往LVEF和ΔLVESV是独立预测因素。真性LBBB（施特劳斯+Predict）患者发生心力衰竭住院的风险显著低于非真性LBBB患者[0.45（0.21-0.90）]，p=0.029。
无论采用施特劳斯还是Predict标准，植入CRT时，真性LBBB患者比非真性LBBB患者有更大的超声心动图反应和更低的心力衰竭住院发生率。
