Cardiac Substrate Utilization and Relationship to Invasive Exercise Hemodynamic Parameters in HFpEF

Area of Science:

• Cardiology
• Metabolic Research
• Biochemistry

Background:

• Heart failure with preserved ejection fraction (HFpEF) is a growing clinical concern.
• Understanding the metabolic alterations in HFpEF is crucial for developing targeted therapies.
• Cardiac energy substrate utilization is altered in various heart conditions.

Purpose of the Study:

• To compare cardiac metabolite and lipid substrate utilization between healthy individuals and those with HFpEF.
• To investigate the influence of hemodynamic factors on cardiac lipid metabolism in HFpEF.
• To identify sex-based differences in cardiac energy substrate use within the HFpEF population.

Main Methods:

• Transcardiac blood sampling was performed in healthy subjects and patients with HFpEF.
• Analysis of cardiac metabolite and lipid substrate use.
• Subgroup analyses were conducted to explore sex-based differences.

Main Results:

• HFpEF hearts demonstrated significantly lower utilization of fatty acids compared to healthy hearts.
• Lipid extraction in HFpEF was found to be influenced by hemodynamic parameters such as pulmonary pressures and cardiac index.
• Increased release of protein catabolism products was observed in HFpEF myocardium.
• Distinct differences in energy substrate utilization were identified between female and male HFpEF subgroups.

Conclusions:

• Cardiac metabolism is significantly altered in HFpEF, with a shift away from fatty acid utilization.
• Hemodynamic status plays a critical role in modulating cardiac lipid metabolism in HFpEF.
• Protein catabolism is elevated, and sex-specific metabolic profiles exist in HFpEF, warranting further investigation.