Department of Cardiology, Leiden University Medical Center, The Netherlands.
Am J Cardiol. 2010 Sep 1;106(5):682-7. doi: 10.1016/j.amjcard.2010.04.026. Epub 2010 Jul 23.
The analysis of left ventricular (LV) mechanics provides novel insights into the effects of cardiac resynchronization therapy (CRT) on LV performance. Currently, advances in speckle-tracking echocardiographic analysis have permitted the characterization of subendocardial and subepicardial LV twist. The aim of this study was to investigate the role of the acute changes in subendocardial and subepicardial LV twist for the prediction of midterm beneficial effects of CRT. A total of 84 patients with heart failure scheduled for CRT were recruited. All patients underwent echocardiography before and <48 hours after CRT implantation and at 6-month follow-up. The assessment of LV volumes, ejection fractions, and mechanical dyssynchrony (systolic dyssynchrony index) was performed with real-time 3-dimensional echocardiography. The assessment of subendocardial and subepicardial LV twist was performed with 2-dimensional speckle-tracking echocardiography. A favorable outcome was defined as the occurrence of a reduction > or =15% in LV end-systolic volume associated with an improvement of > or =1 New York Heart Association functional class at 6-month follow-up. At 6-month follow-up, 53% of the patients showed favorable outcomes. Ischemic cause of heart failure, baseline systolic dyssynchrony index, immediate improvement in the LV ejection fraction, immediate improvement in systolic dyssynchrony index, and immediate improvement in subendocardial and subepicardial LV twist were significantly related to favorable outcomes. However, in multivariate logistic regression analysis, only the immediate improvement of subepicardial LV twist was independently related to favorable outcomes (odds ratio 2.31, 95% confidence interval 1.29 to 4.15, p = 0.005). Furthermore, the immediate improvement of subepicardial LV twist had incremental value over established parameters. In conclusion, the immediate improvement of subepicardial LV twist (but not subendocardial LV twist) is independently related to favorable outcomes after CRT.
左心室（LV）力学分析为心脏再同步治疗（CRT）对 LV 功能的影响提供了新的见解。目前，斑点追踪超声心动图分析的进展已经允许对心内膜下和心外膜下 LV 扭转进行特征描述。本研究旨在探讨心内膜下和心外膜下 LV 扭转的急性变化在预测 CRT 的中期获益中的作用。共招募了 84 例计划接受 CRT 的心力衰竭患者。所有患者在 CRT 植入前和植入后<48 小时以及 6 个月随访时接受了超声心动图检查。使用实时 3 维超声心动图评估 LV 容积、射血分数和机械不同步（收缩不同步指数）。使用 2 维斑点追踪超声心动图评估心内膜下和心外膜下 LV 扭转。将 6 个月随访时 LV 收缩末期容积减少>或=15%，且纽约心脏协会功能分级改善>或=1 级定义为有利结果。在 6 个月随访时，53%的患者出现了有利的结果。心力衰竭的缺血原因、基线收缩不同步指数、LV 射血分数的即刻改善、收缩不同步指数的即刻改善以及心内膜下和心外膜下 LV 扭转的即刻改善与有利结果显著相关。然而，在多变量逻辑回归分析中，只有心外膜下 LV 扭转的即刻改善与有利结果独立相关（比值比 2.31，95%置信区间 1.29 至 4.15，p = 0.005）。此外，心外膜下 LV 扭转的即刻改善具有超过既定参数的增量价值。总之，CRT 后心外膜下 LV 扭转（而非心内膜下 LV 扭转）的即刻改善与有利结果独立相关。
