Porcine heterograft valve replacement in children.

From 1973 to 1980, 49 patients under 18 years of age survived cardiac valve replacement with Hancock porcine heterografts. Complete follow-up has been obtained on 44 patients (90%) in whom 46 valves were placed. There were 30 boys and 14 girls with an age range of 2 to 18 years (mean 10.0 years). Severe prosthetic valvular dysfunction requiring valve replacement occurred in eight valves in seven patients at 15 to 60 months postoperatively (mean 34.1 months), yielding a calculated replacement rate of 7.1% per patient-year. All eight valves demonstrated severe calcification with stenosis, two valves had significant insufficiency secondary to leaflet disruption, and one valve had a large leaflet perforation. Thirty-one patients with valves in place at 7 to 90 months (mean 38.4 months) are alive, but six have clinical evidence of progressive valvular dysfunction. The mean age at the time of the original Hancock valve placement of the group of patients having undergone replacement of a failed prosthesis together with those with clinical evidence of prosthetic dysfunction was 8.0 years, which is significantly less than that of the remaining group of patients with normally functioning valves (mean 11.2 years, p = 0.043). Actuarial curves demonstrate a predicted replacement-free rate of 87.4% +/- 5.9% at 3 years. 82.3% +/- 7.5% at 4 years, and 58.5% +/- 15.7% at 5 years. On the basis of these data and other reports of early failure in the literature, we have discontinued the routine use of Hancock porcine heterografts for cardiac valve replacement in children in favor of mechanical prostheses.