Fate of Left-Sided Cardiac Bioprosthesis Valves in Children

To avoid anticoagulation and minimize thromboembolic phenomena, between 1975 and 1980 we used 18 porcine bioprosthetic valves (BPVs) to replace 11 aortic and seven mitral valves in 17 children ranging from 7 to 18 years of age (mean, 8.2 years). Ten BPVs (91%) in the aortic position had to be replaced one to six years (mean, 4.2 years) after insertion. Nine of these valves developed severe calcification with leaflet immobility and severe stenosis. The tenth valve became insufficient with a disrupted cusp. Six (86%) of seven BPVs inserted in the mitral position required replacement two to four years (mean, 3.1 years) after insertion. Massive mitral regurgitation developed in three, while in the other three mitral stenosis was prominent. All explanted BPVs exhibited calcification with disruption and loss of mobility of the leaflets. Hemodynamic deterioration often occurred catastrophically, with nine patients requiring emergency valve replacement. Elective valve replacement carried no hospital mortality, whereas emergency valve replacement carried a 33% mortality. The BPV failure rate of 94% within six years leads us to recommend against the use of biologic valves in the pediatric age group in the aortic or mitral position. Bioprosthetic valve failure may occur catastrophically and replacement should be carried out early to avoid the higher operative mortality associated with emergency surgery.