HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Add to Personal Folders Download to citation manager Permission Requests Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Gabbay, S. Articles by Cheung, T. K. Search for Related Content PubMed PubMed Citation Articles by Gabbay, S. Articles by Cheung, T. K.

The Journal of Thoracic and Cardiovascular Surgery, Vol 95, 208-215, Copyright © 1988 by The American Association for Thoracic Surgery and The Western Thoracic Surgical Association

ARTICLES

Do heart valve bioprostheses degenerate for metabolic or mechanical reasons?

S Gabbay, P Kadam, S Factor and TK Cheung
Department of Cardiothoracic Surgery, UMDNJ-New Jersey Medical School, Newark 07103.

Although heart valve bioprostheses provide a normal quality of life, their durability is still of great concern. Their durability failure is defined as "degeneration," which is considered to be a consequence of metabolic factors. In this study, we demonstrate that mechanical and design factors can also be responsible for bioprosthesis failure. Large numbers of porcine and pericardial bioprostheses were tested in a fatigue-testing system in which the test conditions were proved to be reproducible and accurate by a laser Doppler anemometer. The results have allowed us to define causes of failure, previously insufficiently stressed, in each type of valve tested. There is a clear difference in factors influencing tissue disruption between porcine and pericardial valves. We have compared these in vitro results with in vivo clinical findings. The main inferences are as follows: (1) Bioprostheses rupture and fail in the same fashion in both in vitro and in vivo studies. (2) Mechanical and design factors are involved in tissue failure. (3) The in vitro/in vivo durability ratio is not 1:1. This ratio depends on the test conditions. (4) Pericardial valves fail because of damage during closure, whereas porcine valves are damaged during both opening and closing (mostly opening) because of design features. (5) Once one cusp fails and prolapses, the other cusps will fail in an accelerated fashion. (6) In vitro durability of 100 X 10(6) cycles can be considered excellent and is an achievable goal. (7) Variability is the key impediment to predicting the durability of bioprostheses. Valves can fail within 2 to 3 million cycles or can last more than 100 million cycles. Similarly, bioprostheses may require explantation within a few months or can last 10 to 13 years in patients. (8) Fatigue testing is an excellent and valuable tool to elucidate the mechanical factors responsible for this variability.

This article has been cited by other articles:

				P. Simon, M.T. Kasimir, G. Seebacher, G. Weigel, R. Ullrich, U. Salzer-Muhar, E. Rieder, and E. Wolner Early failure of the tissue engineered porcine heart valve SYNERGRAFTTM in pediatric patients Eur. J. Cardiothorac. Surg., June 1, 2003; 23(6): 1002 - 1006. [Abstract] [Full Text] [PDF]

				R. W.M. Frater The Carpentier-Edwards Pericardial Aortic Valve: Intermediate Results Ann. Thorac. Surg., December 1, 1998; 66(6): 2153 - 2154. [Full Text] [PDF]

				K. Nakano, K. Eishi, Y. Kosakai, F. Isobe, Y. Sasako, S. Nagata, H. Ueda, Y. Kito, and Y. Kawashima TEN-YEAR EXPERIENCE WITH THE CARPENTIER-EDWARDS PERICARDIAL XENOGRAFT IN THE TRICUSPID POSITION J. Thorac. Cardiovasc. Surg., March 1, 1996; 111(3): 605 - 612. [Abstract] [Full Text]

				G. L. Grunkemeier, W. R. Eric Jamieson, D. C. Miller, and A. Starr Actuarial versus actual risk of porcine structural valve deterioration J. Thorac. Cardiovasc. Surg., October 1, 1994; 108(4): 709 - 718. [Abstract] [Full Text]