[Follow-up study of porcine bioprosthetic valve replacement in 15 children].

GD-I porcine bioprosthetic valve replacement were performed in 15 cases from Jul. 1978 to Nov. 1982. Pathology: RHD 11, CHD 4, 13 with MVR, 1 AVR, 1 TVR. One patient died during operation (operative mortality 6.7%). 13 cases were followed up for 3-10 years: in the early years the symptoms and cardiac function were greatly improved and the size reduced. However dysfunction of bioprosthetic valve was detected 2-8 years after operation in 12 patients (19.37%/patient year). The main cause of damage and dysfunction of porcine valve is calcification of the leaflet. As compared with the adult group(dysfunction rate 3.6%/patient year) in this institute, more calcification of the porcine valve in children is considered because of: (1) stronger metabolism of calcium in children, (2) less mobility of the leaflet due to lower cardiac output in children, and (3) stronger immunoreaction to porcine valve in children.