Cape Town solution in prolonged myocardial preservation: structural and ultrastructural study

Area of Science:

• Cardiology
• Transplantation Biology
• Cellular Pathology

Background:

• Myocardial preservation is critical for successful heart transplantation.
• Hypothermic oxygenated perfusion aims to minimize ischemic injury.
• The efficacy of specific preservation solutions like Cape Town (CT) solution requires detailed evaluation.

Purpose of the Study:

• To assess morphological changes in canine myocardium after 24-hour hypothermic oxygenated perfusion with CT solution.
• To correlate these changes with solution composition and immediate post-transplant hemodynamic function.
• To identify potential improvements for myocardial preservation solutions and reperfusion strategies.

Main Methods:

• Orthotopic heart transplantation in dogs.
• 24-hour continuous hypothermic and oxygenated perfusion using CT solution.
• Morphological analysis of myocardial tissue post-preservation and post-reperfusion.
• Assessment of immediate hemodynamic parameters.

Main Results:

• Preservation induced mild-to-moderate mitochondrial changes, edema, and vasoconstriction.
• Reperfusion led to necrosis with contraction bands, increased mitochondrial damage, prominent edema with hemorrhage, and severe vasoconstriction.
• Intercalated disks remained structurally intact; inflammatory cells infiltrated the interstitium.

Conclusions:

• Cape Town solution requires colloid addition for improved myocardial preservation.
• Reperfusion strategies should selectively address vasoconstriction and inflammation.
• Optimizing preservation solutions and reperfusion protocols is essential for reducing post-transplant myocardial injury.