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Updated: Aug 21, 2026
Isolation of Human Primary Valve Cells for In vitro Disease Modeling
Published on: April 16, 2021
Impact of processing on surface structure of human cardiac valve allografts
Otakar Krs1, Dása Slízová, Jan Burkert
1Charles University in Prague, Faculty of Medicine in Hradec Králové, Department of Anatomy, Czech Republic. krs@lfhk.cuni.cz
Insights
Processing and cryopreservation significantly impact allograft heart valve (AHV) morphology. Scanning electron microscopy revealed endothelial damage during preservation, highlighting the need for optimized AHV banking protocols.
Area of Science:
- Biomaterials Science
- Tissue Engineering
- Cardiovascular Surgery
Background:
- Biological heart valve prostheses require robust processing and preservation for long-term clinical success.
- Current allograft heart valve (AHV) banking protocols may affect tissue integrity.
- Understanding morphological changes is crucial for improving AHV viability and function.
Purpose of the Study:
- To evaluate the impact of standard AHV banking protocols on valve tissue morphology.
- To compare the morphological integrity of AHVs preserved under different conditions.
- To assess the suitability of scanning electron microscopy (SEM) for evaluating AHV processing.
Main Methods:
- Comparison of AHVs from heart-beating and non-heart-beating donors.
- Evaluation of valves preserved in saline and antibiotic solutions.
- Assessment of cryopreserved AHVs stored in liquid nitrogen.
- Sample preparation using hexamethyldisilazane (HMDS) drying and gold coating.
- Morphological analysis via scanning electron microscopy (SEM).
Main Results:
- Distinct superficial patterns were observed on ventricular and vascular surfaces of fresh semilunar valves.
- Early endothelial changes were detected post-harvesting.
- Denudation of endothelial covering occurred during preservation, both with and without freezing.
- The HMDS drying method proved effective for thin human semilunar valve membranes.
Conclusions:
- SEM is a valuable tool for the morphological assessment of AHV processing, cryopreservation, and storage.
- Current preservation methods can lead to endothelial damage in AHVs.
- Further research integrating morphological data with other methods is needed to refine AHV handling protocols.
Abstract:
Methods of processing and cryopreservation are believed to be the most important factors of long term clinical performance of biological heart valve prostheses. That is why we decided to cooperate in evaluating the impact of current AHV (allograft heartvalve) bank protocol on valve tissue morphology. AHV harvested from "heart-beating" cadaveric donors, considered as a fresh tissue, were compared with valve samples from non-heart beating donors, samples stored in saline, samples treated with antibiotic solution, and finally with cryopreserved valves, stored in liquid nitrogen for months. All samples were dissected, dried with hexamethyldisilazane (HMDS) method, gold-coated, studied and photographed in scanning electron microscope Tesla BS 301. Different superficial patterns were found on ventricular and vascular surfaces of "fresh" semilunar valves. We were able to detect early changes of endothelium after harvesting, denudation of endothelial covering during preservation with and without freezing. Our alternative method of drying samples by HMDS method proved to be suitable for thin membranes of human semilunar valves. Scanning electron microscopy seems to be helpful for morphological control of processing, cryopreservation and liquid nitrogen storage of AHV. We believe that further confrontation of morphological investigation with other methods helps us to develop more suitable protocol of handling AHV in heart valve banking.
