The use of echocardiography for the evaluation of dyssynchrony.

Tissue Doppler imaging (TDI), is a new imaging tool that allows measurement of dyssynchrony. In several small studies, TDI predicted clinical response and reverse remodeling after cardiac resynchronization therapy (CRT). Moreover, it allowed detection of mechanical dyssynchrony in heart failure patients with narrow QRS. Using TDI, the selection criteria for CRT might be changed to include heart failure patients with narrow QRS. Furthermore, it will help predict responders to this therapy, hence decreasing the percentage of nonresponders and allowing a more cost-effective use of this new technology.