Advances in Clinical and Experimental Medicine

Title abbreviation: Adv Clin Exp Med
JCR Impact Factor (IF) – 1.727
Index Copernicus  – 166.39
MEiN – 70 pts

ISSN 1899–5276 (print)
ISSN 2451-2680 (online)
Periodicity – monthly

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Advances in Clinical and Experimental Medicine

2018, vol. 27, nr 8, August, p. 1033–1036

doi: 10.17219/acem/73713

Publication type: original article

Language: English

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Structural changes arising from different thawing protocols on cryopreserved human allograft’s aortic valve leaflets

Robert Novotný1,2,3,A,B,C,D,E,F, Dáša Slížová4,C, Jaroslav Hlubocký1,2,E,F, Otakar Krs4,B,C, Jaroslav Špatenka5,6,A,E, Jan Burkert5,6,B,C, Radovan Fiala6,7,B, Petr Mitáš1,2,D,E, Pavel Mĕricka8,E,F, Miroslav Špaček1,2,B, Zuzana Hlubocká2,8,9,E, Jaroslav Lindner1,2,A,F

1 2nd Department of Cardiovascular Surgery, General University Hospital, Prague, Czech Republic

2 1st Faculty of Medicine, Charles University, Prague, Czech Republic

3 Transplant Surgery Department, Institute for Clinical and Experimental Medicine, Prague, Czech Republic

4 Department of Anatomy, Faculty of Medicine, Charles University, Hradec Králové, Czech Republic

5 Transplant Center, University Hospital Motol, Prague, Czech Republic

6 Department of Cardiovascular Surgery, Faculty Hospital Motol, Prague, Czech Republic

7 2nd Faculty of Medicine, Charles University, Prague, Czech Republic

8 Tissue Bank, Faculty Hospital Hradec Králové, Faculty of Medicine, Charles University, Czech Republic

9 2nd Internal Department of Cardiology and Angiology, General University Hospital, Prague, Czech Republic


Background. The aim of our experimental work was to assess the impact and morphological changes that arise during different thawing protocols on human aortic valve (AV) leaflets resected from cryopreserved aortic root allografts (CARAs).
Objectives. Two thawing protocols were tested: 1. CARAs were thawed at a room temperature (23°C); 2. CARAs were placed directly into a water bath at a temperature of 37°C. After all the samples were thawed, non-coronary AV leaflets were sampled from each specimen and fixed in a 4% formaldehyde solution before they were sent for morphological analysis.
Material and Methods. All the samples were washed in distilled water for 5 min and dehydrated in a graded ethanol series (70%, 85%, 95%, and 100%) for 5 min at each level. The tissue samples were then immersed in 100% hexamethyldisilazane (HMDS) for 10 min, and then air-dried in an exhaust hood at room temperature. Processed samples were mounted on stainless steel stubs and coated with gold. Histological analysis was performed with the use of an electron microscope on a scanning mode operating at 25 kV – BS 301.
Results. Thawing protocol 1 (room temperature at 23°C): 6 (100%) samples showed loss of the endothelial covering of the basal membrane with no damage to the basal lamina. Thawing protocol 2 (water bath at 37°C): 5 (83%) samples showed loss of the endothelial covering of the basal membrane with no damage to the basal lamina. One (17%) sample showed loss of the endothelial covering the basal membrane with significant damage to the basal membrane.
Conclusion. Based on our experimental work, we can clearly conclude that cryopreserved AV leaflet allografts show identical structural changes at different rates of thawing.

Key words

aortic valve, allograft, thawing, cryopreserved, structural changes

References (20)

  1. Murray G. Homologous aortic-valve-segment transplants as surgical treatment for aortic and mitral insufficiency. Angiology. 1956;7(5):466–471.
  2. Heimbecker RO. Durability of fresh homograft. Ann Thorac Surg. 1986;42(5):602–603.
  3. Lam CR, Aram HH, Munnell ER. An experimental study of aortic valve homografts. Surg Gynecol Obstet. 1952;94(2):129–135.
  4. Kerwin AG, Lenkei SC, Wilson DR. Aortic valve homograft in the treatment for aortic and mitral insufficiency. N Eng J Med. 1962;266:852–857.
  5. Ross DN. Homograft replacement of the aortic valve. Lancet. 1962;2(7254):487.
  6. Brewin EG. The use of tissue transplants in the surgery of cardiac valve disease: An experimental study. Guys Hosp Rep. 1956;105(3):328–329.
  7. Merin G, McGoon DC. Reoperation after insertion of aortic homograft as a right ventricular outflow tract. Ann Thorac Surg. 1973;16(2):122–126.
  8. Brockbank KG, Schenke-Layland K, Greene ED, et al. Ice-free cryopreservation of heart valve allografts: Better extracellular matrix preservation in vivo and preclinical results. Cell Tissue Bank. 2012;13(4):663–671. doi: 10.1007/s10561-011-9288-7
  9. Gerson CJ, Elkins RC, Goldstein S, Heacox AE. Structural integrity of collagen and elastin in SynerGraft® decellularized-cryopreserved human heart valves. Cryobiology. 2012;64(1):33–42. doi: 10.1016/j.cryobiol.2011.11.001
  10. Moussa M, Dumont F, Perrier-Cornet JM, Gervais P. Cell inactivation and membrane damage after long-term treatments at sub-zero temperature in the supercooled and frozen states. Biotechnol Bioeng. 2008;101(6):1245–1255. doi: 10.1002/bit.21981
  11. Jashari R, Van Hoeck B, Ngakam R, Goffin Y, Fan Y. Banking of cryopreserved arterial allografts in Europe: 20 years of operation in the European Homograft Bank (EHB) in Brussels. Cell Tissue Bank. 2013;14(4):589–599. doi: 10.1007/s10561-012-9359-4
  12. Krs O, Burkert J, Slízová D, Kobylka P, Špatenka J. Allograft semilunar cardiac valves processing and cryopreservation – mor-phology in scanning electron microscope. Cell Tissue Bank. 2006;7(3):167–173.
  13. Nappi F, Al-Attar N, Spadaccio C, Chello M, Lusini M, Acar C. Aortic valve homograft: 10-year experience. Surg Technol Int. 2014;24:265–272.
  14. Heng WL, Albrecht H, Chiappini P, Lim YP, Manning L. International heart valve bank survey: A review of processing practices and activity outcomes. J Transplant. 2013;2013:163150. doi: 10.1155/2013/163150
  15. Fukushima S, Tesar PJ, Pearse B, et al. Long-term clinical outcomes after aortic valve replacement using cryopreserved aortic allograft. J Thorac Cardiovasc Surg. 2014;148(1):65–72.e2. doi: 10.1016/j.jtcvs.2013.07.038
  16. Böll BM, Vogt F, Boulesteix AL, Schmitz C. Gender mismatch in allograft aortic valve surgery. Interact Cardiovasc Thorac Surg. 2015;21(3):329–335. doi: 10.1093/icvts/ivv151
  17. Steffen V, Marsch G, Burgwitz K, Kuehn C, Teebken OE. Resistance to infection of long-term cryopreserved human aortic valve allografts. J Thorac Cardiovasc Surg. 2016;151(5):1251–1259. doi: 10.1016/j.jtcvs.2015.11.029
  18. Neumann A, Cebotari S, Tudorache I, Haverich A, Sarikouch S. Heart valve engineering: Decellularized allograft matrices in clinical practice. Biomed Tech (Berl). 2013;58(5):453–456. doi: 10.1515/bmt-2012-0115.
  19. Tudorache I, Theodoridis K, Baraki H, et al. Decellularized aortic allografts versus pulmonary autografts for aortic valve re-placement in the growing sheep model: Haemodynamic and morphological results at 20 months after implantation. Eur J Cardiothorac Surg. 2016;49(4):1228–1238. doi: 10.1093/ejcts/ezv362
  20. da Costa FD, Costa AC, Prestes R, et al. The early and midterm function of decellularized aortic valve allografts. Ann Thorac Surg. 2010;90(6):1854–1860. doi: 10.1016/j.athoracsur.2010.08.022