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Benefits of Cardiac Resynchronization Therapy in an Asynchronous Heart Failure Model Induced by Left Bundle Branch Ablation and Rapid Pacing
Published on: December 11, 2017
Echo Doppler parameters predict response to cardiac resynchronization therapy
F Wiesbauer1, C Baytaroglu, D Azar
1Department of Cardiology, Vienna General Hospital, Medical University of Vienna, Austria. franz.wiesbauer@meduniwien.ac.at
Echocardiography parameters like Q-to-E-wave-delay (QED) and interventricular mechanical delay (IVMD) can predict patient response and survival after cardiac resynchronization therapy (CRT). These simple measurements offer valuable prognostic insights for CRT candidates.
Area of Science:
- Cardiology
- Medical Imaging
- Heart Failure Management
Background:
- Cardiac resynchronization therapy (CRT) improves outcomes in heart failure but lacks response prediction in ~30% of patients.
- Identifying non-responders to CRT is crucial for optimizing patient management and resource allocation.
Purpose of the Study:
- To evaluate the predictive value of specific Echo Doppler parameters for reverse remodeling, functional improvement, and mortality in CRT recipients.
- To determine if echocardiographic measurements can identify patients likely to benefit from CRT.
Main Methods:
- A cohort of 200 heart failure patients undergoing CRT were assessed for ventricular dyssynchrony using echocardiography.
- Patients were followed for a mean of 10 months to evaluate reverse remodeling and vital status.
Main Results:
- Q-to-E-wave-delay (QED) >550 ms, interventricular mechanical delay (IVMD) >60 ms, and aortic electromechanical delay (A-EMD) >140 ms significantly predicted reverse remodeling.
- QED and IVMD also independently predicted all-cause mortality in CRT patients.
- These findings remained significant after adjusting for potential confounders.
Conclusions:
- QED and IVMD are valuable echocardiographic predictors of reverse remodeling and survival post-CRT.
- These easily obtainable parameters provide crucial prognostic information for CRT candidates.
- Routine measurement of QED and IVMD in echocardiographic evaluations for CRT is recommended.
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