Reassessment of usefulness of porcine heterografts in mitral position in children.

The use of porcine heterograft valves in children is restricted because of valve calcification and dysfunction at follow-up. Because of inability to monitor the anticoagulant status or of desire of some teenage girls to get married and get pregnant, several pediatric patients received porcine heterografts. The purpose of this paper is to examine the issue of heterografts in children, based on our experience with children and adolescents, aged 1 to 20 years, who underwent left heart valve replacement during a 7-year period ending April 1985. Ninety-four percent of the lesions were rheumatic in origin, 4% congenital, and 2% infectious. Of 168 mitral valves replaced, 54 (32%) were porcine heterografts and 114 (68%) were mechanical valves. These were divided into four groups, based on type of valve implanted and age at implantation: mechanical (M), age greater than 15 years (M greater than 15), 49 cases; heterografts (H) age greater than 15 years (H greater than 15), 34 cases; mechanical, age less than or equal to 15 years (M less than or equal to 15), 65 cases; and heterografts, age less than or equal to 15 years (H less than or equal to 15), 20 cases. None of the patients with heterografts received anticoagulation. Five-year actuarial valve survival was 86% for M greater than 15, 96% for H greater than 15, 82% for M less than or equal to 15, and 60% for H less than or equal to 15. The respective 9-year valve survival was 86%, 72%, 75%, and 18%.(ABSTRACT TRUNCATED AT 250 WORDS)