Two-dimensional, non-Doppler strain imaging during anesthesia and cardiac surgery.

Transesophageal echochardiography (TEE) has become an essential intraoperative monitor during general anesthesia for cardiac surgical procedures. In clinical practice, ventricular function is visually evaluated using gray scale and Doppler modes, despite the fact that subjective interpretation is influenced by level of experience and training. Echocardiographic strain imaging measures cardiac deformation and provides objective quantification of regional myocardial function. Non-Doppler strain, which is derived by tracking speckles from two-dimensional (2D) images, bypasses the limitations of Doppler-based strain measurements and evaluates the complex myocardial deformation along three dimensions. As a result, longitudinal shortening, circumferential thinning and radial thickening can be quantified using standard midesophageal and transgastric views, being acquired during a comprehensive TEE examination. Once non-Doppler strain becomes available on "real time," it will have the potential to become a valuable tool for detection of ischemia on the regional level and objective quantification of global ventricular function.