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

Abstract

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±15years; 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 42months, EF increased by 5% (-1% to 15%; P