Department of Cardiology, Leiden University Medical Center, Leiden, The Netherlands.
Circ Cardiovasc Imaging. 2010 Jan;3(1):86-93. doi: 10.1161/CIRCIMAGING.109.882324. Epub 2009 Nov 17.
Left ventricular (LV) fibrosis is important for the response to cardiac resynchronization therapy (CRT). Calibrated integrated backscatter derived by 2D echocardiography quantifies myocardial ultrasound reflectivity, which may provide a surrogate of LV fibrosis. The aim of the study was first, to investigate the relation of myocardial ultrasound reflectivity assessed with calibrated integrated backscatter on CRT response, and second, to explore the "myocardial ultrasound reflectivity-CRT response" relation in patients with ischemic and nonischemic heart failure (HF).
One hundred fifty-nine patients with HF referred for CRT underwent an extensive echocardiographic evaluation at baseline and at 6-month follow-up. LV dyssynchrony was derived from speckle-tracking analysis. Calibrated integrated backscatter was obtained from the parasternal long-axis view. The mean value of calibrated integrated backscatter of the anteroseptal and posterior wall was used to estimate myocardial ultrasound reflectivity. CRT response was defined as reduction >/=15% of LV end-systolic volume. At baseline, LV dyssynchrony was significantly larger in responders as compared with nonresponders (188+/-96 ms versus 115+/-68 ms, P<0.001), and CRT responders showed less myocardial ultrasound reflectivity as compared with nonresponders (-20.8+/-3.0 dB versus -17.0+/-3.0 dB, P<0.001). In multivariable logistic regression analysis, independent predictors for CRT response were LV dyssynchrony, renal function, and myocardial ultrasound reflectivity. Importantly, myocardial ultrasound reflectivity provided an incremental value to CRT response (chi(2) change=40, P<0.001). Considering patients with ischemic HF, the only independent predictor of CRT response was myocardial ultrasound reflectivity, whereas in patients with nonischemic HF, independent predictors of LV reverse remodeling were myocardial ultrasound reflectivity, LV dyssynchrony, and renal function.
Assessment of myocardial ultrasound reflectivity is important in the prediction of CRT response in ischemic and nonischemic patients.
左心室（LV）纤维化对于心脏再同步治疗（CRT）的反应很重要。二维超声心动图定量评估的校正积分背向散射可量化心肌超声反射率，这可能是 LV 纤维化的替代指标。本研究的目的首先是研究心肌超声反射率与 CRT 反应之间的关系，其次是探讨缺血性和非缺血性心力衰竭（HF）患者的“心肌超声反射率-CRT 反应”关系。
159 名因 HF 而接受 CRT 的患者在基线和 6 个月随访时接受了广泛的超声心动图评估。LV 不同步性由斑点追踪分析得出。从胸骨旁长轴获得校正积分背向散射。使用前间隔和后间隔壁的校正积分背向散射平均值来估计心肌超声反射率。CRT 反应定义为 LV 收缩末期容积减少> = 15%。在基线时，与非反应者相比，反应者的 LV 不同步性显著更大（188±96ms 与 115±68ms，P<0.001），并且反应者的心肌超声反射率较非反应者更低（-20.8±3.0dB 与-17.0±3.0dB，P<0.001）。在多变量逻辑回归分析中，CRT 反应的独立预测因素是 LV 不同步性、肾功能和心肌超声反射率。重要的是，心肌超声反射率为 CRT 反应提供了额外的价值（chi(2)变化=40，P<0.001）。考虑到缺血性 HF 患者，CRT 反应的唯一独立预测因素是心肌超声反射率，而非缺血性 HF 患者的 LV 逆重构的独立预测因素是心肌超声反射率、LV 不同步性和肾功能。
在缺血性和非缺血性患者中，评估心肌超声反射率对于预测 CRT 反应很重要。
