Long‐Term Response of the Left Ventricle to Cardiac Resynchronization Therapy: Insights From Standard and Strain Echocardiography

Congest Heart Fail. 2011;17:70–78. ©2011 Wiley Periodicals, Inc. Left ventricular (LV) response to cardiac resynchronization therapy (CRT) has typically been studied over 3‐ to 12‐month periods. Longer‐term data are unclear and response of strain parameters has not been reported. The authors evaluated long‐term response with standard and strain echocardiography in 57 patients (52±15 years; 40 male; 30 white; 15 with ischemic etiology) who received a CRT‐defibrillator between January 2004 and December 2005. Median ejection fraction (EF) at baseline was 22% (17%–25%). Global longitudinal, radial, and circumferential strain were −6.5% (−5.0% to −8.4%), 10.4% (6.9%–15.1%), and −7.6% (−5.5% to −10.8%), respectively. After a median of 42 months, EF increased by 5% (−1% to 15%; P