Service de Cardiologie et CIC-IT INSERM 1414, CHU Pontchaillou - Rennes, 2 Rue Henri Le Guilloux, Rennes, France.
LTSI, Université de Rennes 1 - INSERM, UMR 1099 - Rennes, Rennes, France.
Eur Heart J Cardiovasc Imaging. 2018 Sep 1;19(9):1010-1018. doi: 10.1093/ehjci/jex191.
Cardiac resynchronization therapy (CRT) plays a pivotal role in the management of patients with heart failure (HF) and wide QRS complex. However, the treatment is plagued by numerous non-responders. Aim of the study is to evaluate the role myocardial work estimated by pressure-strain loops (PSLs) in the comprehension of physiological mechanisms associated with CRT and in the prediction of CRT response.
Ninety-seven patients with symptomatic HF (ejection fraction: 27 ± 6%, QRS duration 164 ± 18 ms) undergoing CRT implantation according to current recommendations were retrospectively included in the study. Standard 2D and speckle tracking echocardiography were performed before CRT and at the 6-month follow-up (FU). PSL analysis allowed the calculation of global and regional myocardial constructive work (CW) and wasted work (WW). A > 15% reduction in left ventricular (LV) end-systolic volume at FU defined CRT-positive response (CRT-PR). At FU, 63 (65%) patients responded to CRT. Global CW (CWtot) was significantly increased in CRT-responders. At multivariate analysis, CWtot > 1057 mmHg% (OR 14.69, P = 0.005) and septal flash (OR 8.05, P = 0.004) were the only significant predictors of CRT-PR. CWtot was associated with the entity of CRT-induced myocardial remodelling in both ischaemic (r = -0.55, P < 0.0001) and non-ischaemic patients (r = 0.65, P < 0.0001). A CWtot < 1057 mmHg% identified 85% of non-responders with a positive predictive value of 88%.
Patients with higher CWtot exhibit a favourable response to CRT. These data encourage further studies for the assessment of the myocardial substrate related to the functional response to CRT.
心脏再同步治疗（CRT）在心力衰竭（HF）和宽 QRS 复合物患者的治疗中起着关键作用。然而，该治疗方法存在大量无反应者。本研究旨在评估压力-应变环（PSL）估计的心肌做功在理解 CRT 相关生理机制和预测 CRT 反应中的作用。
本研究回顾性纳入 97 例根据当前建议接受 CRT 植入的有症状 HF 患者（射血分数：27±6%，QRS 持续时间 164±18ms）。在 CRT 植入前和 6 个月随访（FU）时进行标准二维和斑点追踪超声心动图检查。PSL 分析可计算整体和局部心肌构建功（CW）和浪费功（WW）。FU 时左心室（LV）收缩末期容积减少>15%定义为 CRT 阳性反应（CRT-PR）。FU 时，63（65%）例患者对 CRT 有反应。CRT 反应者的整体 CW（CWtot）显著增加。多变量分析显示，CWtot>1057mmHg%（OR 14.69，P=0.005）和室间隔闪光（OR 8.05，P=0.004）是 CRT-PR 的唯一显著预测因素。CWtot 与缺血（r=-0.55，P<0.0001）和非缺血患者（r=-0.65，P<0.0001）的 CRT 诱导心肌重塑程度相关。CWtot<1057mmHg%可识别 85%的无反应者，阳性预测值为 88%。
CWtot 较高的患者对 CRT 有较好的反应。这些数据鼓励进一步研究评估与 CRT 功能反应相关的心肌底物。
