Structural failure of pyrolytic carbon heart valves

Pyrolite carbon has been used for the manufacture of mechanical heart valve prostheses for the past 25 years. In general, pyrolytic carbon mechanical heart valves have provided adequate physiological function and satisfactory structural performance. Although rare in occurrence, incidents of valve failure due to fracture of one or more components have been reported. These reports of failure are reviewed and a few representative examples are examined in detail in order to determine the characteristic failure mechanism. Understanding the underlying factors responsible for causing these failures provides a solid basis for improved design and manufacture of future mechanical heart valve prostheses.