Echocardiographic algorithm for cardiac resynchronization.

Cardiac resynchronization therapy (CRT) has become a proven therapeutic strategy for refractory heart failure. Large clinical trials have shown a reduction in both morbidity and mortality in patients treated with CRT. Initial patient selection has relied mainly on electrocardiographic criteria that allowed identifying only 70% of responders. Accordingly, echocardiographic criteria were developed to identify dyssynchrony in the hope of improving patient selection. Multiple echocardiographic criteria have since been proposed, with no consensus as to which parameter better predicts CRT response. Although comparison studies using the different criteria are underway, the current evaluation of dyssynchrony should probably be an integrated multiparameter approach. The objective of this article is to review the role of echocardiography in the evaluation of cardiac dyssynchrony and propose a practical algorithm in order to improve CRT patient selection.