Extended Preservation of Heart Grafts: LYPS Solution Maintains Cardiac Function During 20-Hour Static Cold Storage

Area of Science:

• Cardiology
• Transplantation Immunology
• Biochemistry

Background:

• Heart transplantation success is limited by donor organ shortages and damage from ischemia-reperfusion injury.
• Current preservation solutions inadequately maintain myocardial viability, impacting post-transplant function.
• Standardized strategies are needed to improve donor heart preservation.

Purpose of the Study:

• To evaluate an improved preservation solution, LYPS (Lyon Preservation Solution), for its efficacy in protecting myocardial grafts.
• To compare LYPS against established solutions (Celsior, St. Thomas) in preserving heart function and viability.
• To investigate LYPS's effects on mitochondrial function and electrophysiology during cold storage and reperfusion.

Main Methods:

• In vitro assessment of extracellular solutions on cardiac cell lines (H9C2) under simulated ischemia-reperfusion.
• Ex vivo evaluation of LYPS, Celsior, and St. Thomas solutions in isolated pig hearts subjected to cold static storage.
• Assessment of heart function, mitochondrial viability, and cardiomyocyte electrophysiology post-preservation.

Main Results:

• LYPS demonstrated superior protection against cell death and mitochondrial membrane potential loss compared to Celsior and St. Thomas solutions.
• LYPS outperformed St. Thomas in preserving mitochondrial function and limiting troponin I release.
• LYPS-treated hearts exhibited improved functional recovery, contractility, and rhythmicity upon reperfusion.

Conclusions:

• LYPS effectively preserves myocardial viability and function during long-term cold storage, outperforming current standards.
• The solution shows promise for enhancing donor heart quality and improving heart transplantation outcomes.
• Potential mechanisms involve modulation of the repolarizing IK1 current and mitochondrial metabolic activation.