Cytotoxicity of amphotericin B for fibroblasts in human heart valve leaflets

The cytotoxicity of amphotericin B (Fungizone, containing deoxycholate) was investigated for human heart valve leaflet fibroblasts. Leaflets were obtained from human aortic and pulmonic valves and incubated in culture medium containing amphotericin B. Upon completion of incubation, some leaflet sets were analyzed immediately, and others were cryopreserved and stored below -135 degrees C. Quantitative fibroblast viability assays were performed. The results can be summarized by consideration of the data obtained from autoradiographic analysis of [3H]proline incorporation into collagen. Incubation with 10 micrograms/ml amphotericin B at 37 degrees C resulted in approximately 11% loss of fibroblast viability. After cryopreservation, the leaflets incubated with amphotericin B experienced an additional 42% loss of fibroblast viability. These results indicate that use of amphotericin B, in this form, is ill advised for treatment of human heart valves prior to cryopreservation.