长轴和整体应变评估左室舒张功能不全模型

Assessment of left ventricular diastolic dysfunction with longitudinal /global strain by speckle tracking

目的探讨超声二维长轴应变和整体应变评估左室舒张功能不全的实验研究。方法采用心导管、超声诊断仪测量实验模型的左室压力、压力最大变化速率、室壁厚度、左室射血分数等指标,运用斑点追踪测量起搏过程中长轴峰值应变、整体应变指标。方法实验犬安置起搏器后的左室舒张末压较起搏前有逐渐增长的趋势。随着起搏时间的延长,左室腔内压力最大上升和下降速率均呈下降趋势,实验犬心肌各段的二维长轴应变和整体应变呈逐渐减低的趋势,部分终末时间段的测量值显著低于基础状态(P<0.05)。其中二维长轴应变和整体应变与左室舒张末压和左室腔内压力最大下降速率呈正相关。结论斑点追踪技术测量的二维长轴应变和整体应变与左室舒张功能下降呈正相关,对于早期评价左室舒张功能降低具有研究价值。

Objective To explore the assessment of left ventricular diastolic dysfunction with longitudinal/global by 2D speckle tracking echocardiography （STE）. Methods Left ventricular pressures, peak rates of LV pressure rise and de- cline,longitudinal strain and left ventricular ejection fraction of the models were analyzed by cardiac catheter and diasono- graph. Longitudinal peak strain and global strain were measured by using STE. Results Left ventricular end-diastolic pressure steadily increased with the time after placement of pacemaker. Peak rates of LV pressure rise and decline steadily increased with the time after placement of pacemaker. However, the longitudinal peak strain and global strain decreased significantly（ P 〈 O. 05 ）. There were correlations among LVEDP, - dP/dtmax and the indices of LPS and GS. Conclusion Left ventricular diastolic dysfunction is related with 2D longitudinal peak strain and global strain by speckle tracking imaging. It may be potential sensitive parameters to become clinical tool for quantifying LV diastolic function.