CMR-based cardiac phenotyping in different forms of heart failure

Area of Science:

• Cardiology
• Medical Imaging
• Biomedical Engineering

Background:

• Heart failure (HF) is a complex condition with diverse pathophysiological mechanisms.
• Accurate characterization of HF subtypes, including heart failure with preserved (HFpEF), mid-range (HFmrEF), and reduced ejection fraction (HFrEF), is crucial for effective management.
• Current diagnostic tools often lack detailed structural and functional imaging data, necessitating advanced imaging techniques.

Purpose of the Study:

• To investigate the utility of cardiac magnetic resonance (CMR) imaging in characterizing distinct HF phenotypes.
• To elucidate the underlying structural and functional cardiac alterations in HFpEF, HFmrEF, and HFrEF using CMR.
• To explore the potential of CMR-derived parameters for personalized HF management strategies.

Main Methods:

• Inclusion of 22 HFpEF, 17 HFmrEF, 15 HFrEF patients, and 19 healthy volunteers.
• Comprehensive CMR assessment including volumetric analysis of the left atrium (LA) and left ventricle (LV), left atrioventricular coupling index (LACI), and feature-tracking analysis for LA and LV strain (reservoir, conduit, active boosterpump function).
• CMR-based tissue characterization using T1 mapping and late gadolinium enhancement (LGE) to assess myocardial fibrosis.

Main Results:

• HFpEF patients exhibited significant atrial impairment (reduced reservoir and conduit function) and increased LACI compared to controls.
• HFmrEF patients presented with LV enlargement and preserved LA function, with compensatory increase in LA active boosterpump function.
• HFrEF patients demonstrated global LA and LV functional impairment, accompanied by progressive myocardial fibrosis (T1 mapping and LGE) in the order of HFrEF > HFmrEF > HFpEF.

Conclusions:

• CMR imaging provides valuable insights into the distinct pathophysiological profiles of HF phenotypes.
• HFpEF is characterized by primary atrial dysfunction, HFmrEF by ventricular enlargement with atrial compensation, and HFrEF by global impairment and significant LV fibrosis.
• These findings underscore the importance of personalized HF management tailored to imaging-derived phenotypic characteristics.