An NMR probe to study function and metabolism simultaneously in isolated human cardiac tissue

Area of Science:

• Biomedical Engineering
• Cardiovascular Physiology
• Biophysics

Background:

• Donor heart preservation is critical for cardiac transplantation success.
• Assessing the mechanical performance and bioenergetics of cardiac tissues is essential for evaluating preservation methods.
• Existing methods may not simultaneously capture mechanical function and metabolic state.

Purpose of the Study:

• To develop and validate a novel perifusion system coupled with 31P NMR spectroscopy.
• To enable simultaneous measurement of mechanical performance and energetic compounds in human atrial trabeculae.
• To assess the feasibility of this system for studying cardiac preservation.

Main Methods:

• Development of a specialized perifusion system with a fiber optic strain gauge.
• Integration of a double-tuned NMR probe (1H and 31P) for simultaneous measurements.
• Utilized small muscle samples (10-20 mg) at controlled temperatures (4-37°C).

Main Results:

• Achieved quantitative 31P NMR spectra from ~10 mg of human atrial trabeculae in 15 minutes.
• Demonstrated rapid spectral acquisition from mouse muscles (<10 min for 8-12 mg).
• System allows simultaneous assessment of mechanical function and energetic compounds.

Conclusions:

• The developed system is effective for evaluating the mechanical performance and energetic status of small muscle tissues.
• This technique holds promise for advancing research into donor heart preservation strategies.
• The system's versatility supports studies across a range of temperatures and muscle types.