Complex sentence: Beginning in 1979, Bjork-Shiley valves with the convexo-concave design had a tendency to develop fractures in the outflow strut which could result in catastrophic valve failure and possibly sudden cardiac death.
Split into simpler sentences: Beginning in 1979, Bjork-Shiley valves with. The convexo-concave Bjork-Shiley valve had a tendency to develop fractures in the outflow strut which could result in catastrophic valve failure and possibly sudden cardiac death.