SURVIVAL TIMES OF PROVOX(TM) VALVES

This study was performed to assess the survival times of the Provox(TM ) valve in the Manchester area. Thirty-nine patients from four hospita ls, representing 81 valve failures, were studied. The effects of the t iming of the tracheo-oesophageal puncture, previous radiotherapy, and the presence and timing of cricopharyngeal myotomy on valve life were analysed. Regression analysis using an extension of the Cox model to a llow strata showed that the lifetime of the first valve only is advers ely affected by previous radiotherapy. The other covariates do not hav e a statistically significant effect on valve survival. The median val ve survival is 4.5 months, (range one to 12 months). A small percentag e of valve users with particularly frequent valve failures may require additional support and prolonged anti-fungal therapy.