Mitroflow pericardial bioprosthesis: structured failure at 4.5 years.

Prosthetic heart valves are commonly used in the management of significant valvular disease. Although bioprostheses are increasingly popular, structural deterioration with cusp tears and calcification persists.We present a case of a Mitroflow pericardial bioprosthesis (Sorin Group Inc., Mitroflow Division, Vancouver, Canada) explanted after 4.5 years from a 78-year-old woman for bioprosthesis stenosis.The morphological reasons for bioprosthesis failure include structural tissue deterioration with thickening of the pericardial cusps, cusp calcification, and parastent post tears resulting in significant valvular dysfunction.To the best of our knowledge, this is the first detailed morphological description of the failure modes of a surgically explanted Mitroflow (A12) pericardial bioprosthesis.