Imaging for planning of cardiac resynchronization therapy

Area of Science:

• Cardiology
• Biomedical Engineering
• Medical Imaging

Background:

• Cardiac resynchronization therapy (CRT) is a treatment for refractory heart failure (HF).
• CRT improves survival, reduces hospitalizations, and enhances quality of life in HF patients.
• Mechanical dyssynchrony is believed to be the primary mechanism for CRT's benefits.

Purpose of the Study:

• To review the current evidence on CRT efficacy and patient selection.
• To explore the role of cardiac imaging in identifying mechanical dyssynchrony for CRT.
• To address the limitations of QRS duration in predicting CRT response.

Main Methods:

• Systematic review of clinical trials and imaging studies related to CRT.
• Analysis of patient selection criteria based on electrocardiogram (ECG) and cardiac imaging.
• Evaluation of the diagnostic accuracy of various imaging modalities for mechanical dyssynchrony.

Main Results:

• CRT significantly benefits selected HF patients, but 30-40% do not respond.
• QRS duration on ECG is a common but imperfect predictor of CRT response.
• Cardiac imaging shows potential for identifying mechanical dyssynchrony but lacks standardized criteria for CRT selection.

Conclusions:

• Optimal patient selection is crucial for CRT due to its cost and invasiveness.
• Cardiac imaging modalities offer a promising avenue for improving patient selection for CRT.
• Further research is needed to establish validated imaging criteria for CRT candidacy.