Cardiac Resynchronization Therapy in Non-Ischemic Cardiomyopathy
Miriam Shanks1, Victoria Delgado1, Jeroen J Bax1
1University of Alberta, Mazankowski Alberta Heart Institute, Edmonton (Canada) and Heart Lung Center, Leiden University Medical Center, Leiden (The Netherlands).
Journal of Atrial Fibrillation
|December 3, 2016
Summary
Cardiac resynchronization therapy (CRT) improves heart failure outcomes in select patients. Patient cardiac substrate, assessed via imaging, significantly influences CRT response, with non-ischemic cardiomyopathy patients showing better results.
Area of Science:
- Cardiology
- Biomedical Engineering
- Medical Imaging
Background:
- Cardiac resynchronization therapy (CRT) is indicated for symptomatic heart failure patients with reduced ejection fraction and wide QRS duration.
- Patient response to CRT is highly variable and influenced by underlying cardiac conditions and lead placement.
- Understanding the cardiac substrate is crucial for optimizing CRT efficacy.
Approach:
- This review highlights the role of multimodality imaging in assessing cardiac substrate.
- It examines factors influencing CRT response, including mechanical dyssynchrony, myocardial fibrosis, and lead positioning.
- The approach emphasizes comparing outcomes in ischemic versus non-ischemic cardiomyopathy.
Key Points:
- CRT response is dependent on correctable left ventricular mechanical dyssynchrony and the presence/location of myocardial scar.
- Left ventricular lead position is a critical determinant of CRT success.
- Non-ischemic cardiomyopathy patients generally exhibit higher CRT response rates than ischemic cardiomyopathy patients.
Conclusions:
- Multimodality imaging is essential for evaluating the cardiac substrate and predicting CRT response.
- Differences in myocardial substrate between ischemic and non-ischemic cardiomyopathies contribute to variable CRT outcomes.
- Personalized assessment of cardiac substrate can optimize patient selection and improve CRT efficacy.
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