Left atrial function, a new predictor of response to cardiac resynchronization therapy?

Area of Science:

• Cardiology
• Echocardiography
• Heart Failure Management

Background:

• Cardiac resynchronization therapy (CRT) is established for advanced heart failure with prolonged QRS duration.
• CRT improves left ventricular (LV) function and remodeling in many patients.
• However, approximately one-third of patients do not benefit from CRT.

Purpose of the Study:

• To evaluate if left atrial (LA) strain imaging parameters can predict LV reverse remodeling response to CRT.
• To identify novel predictors of CRT success using echocardiographic assessments.

Main Methods:

• Seventy-nine patients undergoing CRT had pre-implantation echocardiography.
• Assessed LA and LV function using M-mode, 2D echocardiography, Doppler, tissue Doppler, and strain imaging (ε).
• Defined LV reverse remodeling as >15% reduction in LV end-systolic volume.

Main Results:

• 68% of patients (54/79) responded to CRT at 6 months.
• LA systolic peak of strain rate (SRA) was significantly associated with CRT response (OR 10.5, P = .01).
• Other predictors included left bundle branch block, ischemic cardiomyopathy, and LV preejection index.

Conclusions:

• Pre-implantation assessment of LA function, particularly SRA, is relevant for predicting CRT response.
• SRA shows promise as a predictor of CRT success.
• Integrating LA function analysis into patient selection for CRT is recommended.