Novel echocardiographic tools for predicting a good response to cardiac resynchronization therapy: a narrative review

Despite significant progress in new echocardiographic techniques, the role of echocardiography in qualifying patients for cardiac resynchronisation therapy (CRT) remains limited solely to the assessment of left ventricular ejection fraction (LVEF). This review aims to present the current knowledge on new echocardiographic methods that may be useful in predicting the response to resynchronization. Recent advances in speckle-tracking echocardiography (STE) have introduced several promising parameters. Measures such as global longitudinal strain, mechanical dispersion, and various indices of mechanical dyssynchrony, including those derived from myocardial work, have shown growing evidence of their utility in identifying patients more likely to benefit from CRT. Increasing data support the use of these deformation-based techniques as complementary tools to traditional LVEF assessment, offering a more precise characterization of left ventricular mechanics and potentially improving patient selection. This paper aims to demonstrate how new echocardiographic techniques allow for the evaluation of relevant left ventricular mechanical dyssynchrony, and to highlight their current and emerging value in the clinical assessment and management of heart failure patients being considered for CRT.