Mechanical failure of the Björk-Shiley valve. Updated follow-up and considerations on prophylactic rereplacement.

The early production series of the 29 to 31 mm 70-degree convexo-concave (CC70) Björk-Shiley heart valves constitutes a subgroup of CC70 values with an extra high risk of outlet strut fracture. The hazard function for mechanical failure among these valves has remained almost constant over a 7-year follow-up period, and the 7-year actuarial incidence of mechanical failure among these valves is 12.5%. Selected patients with these valves will be considered for prophylactic rereplacement.