FDA's requirements for in-vivo performance data for prosthetic heart valves

The Food and Drug Administration (FDA) has recently revised its "Replacement Heart Valve Guidance". That document lists the data FDA deems necessary to support the approval of new prosthetic heart valves of all designs, and which should be contained in Premarket Approval Applications for these devices. The guidance covers detailed data requirements for in vitro, animal, and clinical data. This paper is intended to briefly summarize FDA's requirements for in vivo and clinical data. The clinical study must establish that the device is both safe and effective, as compared to currently marketed replacement heart valves. It is possible to achieve this goal using hypothesis testing to compare the results of an observational study against a set of Objective Performance Criteria (OPC) which have been established by the FDA. The establishment of the OPCs was facilitated by a standardized set of definitions of complications published by the American Association of Thoracic Surgery and Society of Thoracic Surgeons (AATS/STS) in 1987/1988. Papers published in peer reviewed journals have utilized this set of definitions for data analysis, providing an ample pool of data from which to establish OPCs. The number of patients required to establish the safety and efficacy of a replacement heart valve, using this approach, is 800 valve years, 400 in the aortic and 400 in the mitral position. Advantages of this approach are reduction in the number of patients and duration of the study.