Natural history of fascia lata valves in the aortic and mitral positions.

A total of 68 frame-mounted fascia lata valves were inserted in 59 patients between November 1969 and September 1970. The valves were all constructed by one or other of the authors with only minor variations in technique during the period of 10 months when this type of valve replacement was practised. All were mounted on cloth-covered metal frames whose geometry also remained substantially unaltered throughout the series. This report is concerned with the natural history of this type of valve substitute in the aortic and mitral positions. The evidence to date indicates that the frame-mounted fascia lata valve continues to function well in the aortic position for periods of more than two years, whereas in the mitral position the behaviour of the valve is unpredictable with a significant incidence of degenerative change and loss of function within one year of insertion.