Key result
Standard cryopreservation of allograft heart valves damages the extracellular matrix via ice crystal formation.
Why the study?
What are the current aspects and future applications of allograft heart valve preservation methods?
What are the current aspects and future applications of allograft heart valve preservation methods?
Standardized frozen cryopreservation of allograft heart valves causes extracellular matrix damage, suggesting that novel preservation techniques avoiding ice formation may improve long-term valve function.
Current cryopreservation may impair allograft durability; leaves open whether ice-free methods improve outcomes.
Human heart valve allografts continue to represent almost perfect substitutes for heart valves. They have optimal hemodynamic characteristics and are highly resistant to infections. The first clinical use of allograft heart valves was as homovitals being transplanted after antibiotic incubation without any preservation. Since 1968, relatively standardized frozen cryopreservation (SFC) has been employed, including storage in vapor-phase liquid nitrogen. Disadvantages, particularly in pediatric patients, are limited availability due to organ scarcity, inability to grow, degeneration, immune response, and long-term failure. However, in contrast to alternative prosthetic or bioprosthetic heart valve replacements, they represent the best pediatric and juvenile replacement options for the pulmonary valve. Application of multiphoton imaging analysis for three-dimensional visualization of elastin and collagen by induction of autofluorescence without chemical fixation, embedding, and staining has revealed partial destruction of elastic and collagenous matrix in SFC valves. As the overall amount of collagen and elastin remains unchanged, the observed destruction is attributed to freezing-induced extracellular matrix damages due to ice crystal formation during SFC. The objective of this review is an assessment of current allograft preservation methods and the potential of novel preservation techniques to avoid ice formation with accompanied better long-term function.
No takes yet. Share an insight, caveat, or question.
Lisý et al. (2017) conducted a review in Heart valve replacement. Allograft heart valves was evaluated. Standardized frozen cryopreservation of allograft heart valves causes freezing-induced extracellular matrix damage due to ice crystal formation, highlighting the need for novel preservation techniques.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: