Cardioplegia for heart transplantation: unmodified UW solution compared with Stanford solution

Area of Science:

• Cardiology
• Transplantation Biology
• Biochemistry

Background:

• Cold crystalloid cardioplegia is effective for donor heart protection.
• Optimizing myocardial protection is crucial for successful heart transplantation.
• Comparing University of Wisconsin (UW) solution and Stanford (ST) solution is important for improving preservation techniques.

Purpose of the Study:

• To compare the efficacy of unmodified University of Wisconsin (UW) solution versus the dextrose, mannitol-based Stanford (ST) solution for donor heart protection.
• To evaluate myocardial mechanics, energetics, and water content after hypothermic ischemic storage and reperfusion.

Main Methods:

• A canine heart transplantation model was utilized with hypothermic cardioplegic arrest and 6 hours of ischemic storage.
• Isolated working heart preparations were used for reperfusion studies.
• Myocardial function was assessed using pressure-volume loops, and myocardial water content was measured.

Main Results:

• Both UW and ST solutions supported reperfusion, with no significant differences in maximum elastance, preload recruitable stroke work, or end-diastolic pressure-volume curve slope.
• A significant increase in myocardial water content (edema) was observed in both groups after reperfusion and persisted after the working phase.
• The University of Wisconsin (UW) solution group exhibited significantly less marked edema compared to the Stanford (ST) solution group.

Conclusions:

• The University of Wisconsin (UW) solution offers superior protection against postreperfusion myocardial edema compared to the Stanford (ST) solution.
• While both solutions maintain functional recovery, UW solution demonstrates a better safety margin regarding tissue hydration.
• Further research may focus on optimizing UW solution or exploring alternative preservation strategies to minimize reperfusion injury.