[Incidents of malfunction of mechanical heart valves as reported to the German Medical Devices Vigilance System].

BACKGROUND

The purpose of this study was to collect the experience gained from risk assessment of incidents associated with mechanical heart valves as reported to the German Medical Devices Vigilance System.

METHODS

All events in connection with the use of prosthetic heart valves which had been reported to the Federal Institute for Drugs and Medical Products were identified in the Institute's anonymized database. Subsequently all information that had been obtained and the reports of investigations by the various responsible manufacturer of medical products were retrospectively analysed.

RESULTS

Of 53 incident reports the aortic valve position was involved 32 times, the mitral valve position 21 times. 17 cases of leaflet breakage, 12 of leaflet dysfunction, 6 of valve thrombosis, 4 of paravalvular leakage, 4 of damage to the suture ring, 3 of endocarditis and 7 of various other singular defects were reported. The outcome was mostly very serious (re-surgery, prolongation of surgery, death). Corrective actions taken by the manufacturers consisted of recalls, advisory notices and stoppage of production.

CONCLUSIONS

The Medical Devices Vigilance System is able to detect product failures of mechanical heart valves and to initiate corrective action. As the reporting rate over more than 10 years is relatively low, it can be assumed that in general mechanical heart valves are safe medical devices. The quality of incident reporting by manufactures and users of medical devices should be improved to reduce the number of undetected and unsolved incidents.