Relation of Calcification to Torn Leaflets of Spontaneously Degenerated Porcine Bioprosthetic Valves

Abstract

The gross appearance of 54 spontaneously degenerated porcine bioprosthetic valves was evaluated to determine the relation of calcium deposition to cusp disruption. Tears or perforations were shown in 89% (48) of the degenerated valves. The most common site of tears or perforations was near the commissural attachment (60% of all tears). Grossly visible deposits of calcium salts that ruptured to the surface of the cusps or caused changes in the topography were observed in 70% (38) of the 54 valves. Calcification was adjacent to tears or perforations in 56% (27) of the 48 valves with torn cusps. Among the valves that showed calcification, the deposits of calcium salts were adjacent to tears or perforations in 71% (27 of 38). The location of deposits of calcium did not relate to the age or sex of the patient or to the position of the valve, but valves with calcium were inserted longer than valves with no calcium (87 ± 4 versus 58 ± 7 months; p < 0.001). The outflow surfaces showed more calcification than the inflow surfaces, irrespective of whether the valves were in the aortic or mitral position. Among the 38 valves with calcification, 92% (35) showed calcification at the commissural attachments, 53% (20) showed calcification in the body of 1 or more cusps, 11% (4) near the base, and 8% (3) near the free edge. In conclusion, most patients with spontaneous porcine valve degeneration showed calcification. The calcification was associated with tears or perforations of the cusps in 50% of all degenerated valves, in 56% of valves with torn cusps, and in 71% of valves that showed gross calcification.