Requirements-centric closed-loop validation of implantable cardiac devices

Abstract

Implantable medical devices are recommended by physicians to sustain life while improving the overall quality of life of the patients. In spite of the rigorous testing, there have been numerous failures and associated recalls which suggest that completeness of the testing is elusive. We propose a new validation framework based on formal methods for real-time closed-loop validation of medical devices. The proposed approach includes a synchronous observer acting both as an automated oracle and also as a requirements coverage monitor. The observer combines an on-line testing adequacy evaluation module together with a heuristic learning module. This methodology was applied to validate a pacemaker over a virtual heart model. A subset of the requirements was used to test its efficacy. The results show that the proposed methodology can, in real-time, evaluate the test adequacy and hence guide the on-line test case generation to maximize the requirements coverage.