Viability and histopathology of eleven fresh, antibiotic-treated allografts removed three weeks to three years after implantation.

Changes in metabolic activity of removed heart valve allografts have been measured. The fresh heart valves were sterilized and stored in antibiotic solution before implantation in patients. Viability was determined before insertion and after removal from patients by two methods: 1) tissue culture, and 2) autoradiography, using tritiated thymidine. The length of storage in the Hank's antibiotic or nutrient-antibiotic medium before insertion did not seem to influence the final metabolic activity nor the structural integrity of the allografts when they were removed. Results from the present study show that the most severe degenerative changes occur in valves stored in Hank's solution and then implanted in the mitral position. The viability percentage declined progressively during the time that a valve treated in this manner was functioning in a patient.