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Safety Issues with Medtronic Long Range Telemetry Implants. Chris Fuller 6/23/06. Medtronic. An innovative, forward-thinking, wonderful company which has saved many lives. Employs some of the most brilliant and capable engineers and scientists I know.
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Safety Issues with Medtronic Long Range Telemetry Implants Chris Fuller 6/23/06
Medtronic • An innovative, forward-thinking, wonderful company which has saved many lives. • Employs some of the most brilliant and capable engineers and scientists I know. • Managed by individuals unfamiliar with high-reliability RF product development and manufacturing. • Risks patient safety unnecessarily by evaluating their long-range telemetry implants much the same way as older, low-frequency implants. • My Goal: Help Medtronic quietly understand and correct serious RF design evaluation and test issues before someone dies.
Why is RF Different? Minimum Capacitor model for radio frequency circuits Capacitor model for low frequency circuits • Capacitor values and their parasitics change as they age and with • varying voltages, temperatures, humidity, and vibration levels. • Slight changes in capacitor values and parasitics can cause great • changes in circuit performance. • Other types of component types are similarly affected (e.g. transistors, • inductors, resistors, etc.)
Design Verification Highlights • Commercial cell phone basestation manufacturer: • Extensive evaluation of each sub-circuit. • Accelerated Life Testing (ALT) for several weeks. • Use of parts “burned in” BEFORE production. • Detailed production testing of each radio. • Military and NASA: In family with cell phones • Medtronic: • Did not evaluate each sub-circuit as extensively. • Abbreviated, lower stress and unproven ALT. • Less thorough burn in process. • Official production testing less than for cell phone basestations.
RF Stability • RF instability: loss of control of an RF circuit. Can lead to non-functionality, high current mode and/or circuit failure. • Most extensively studied RF parameter for a cell phone radio circuit. • Some indications of instability for Concerto found during DVT, but not reported. • Medtronic stability verification for Concerto is substandard and incomplete. • Concerto has unacceptably high unknown risk for instabilities
Medtronic Regulatory Issues • Medtronic has a history of non-compliance with regulatory rules. • In violation of FCC rules for all CRM implants and programmers in-service prior to FCC R&O FCC-03-149A1 on June 25, 2003. • Medtronic V.P. for Regulatory affairs reported that Medtronic would rather pay a fine than comply with their regulatory requirements. • Medtronic submitted a fraudulent SAR report to the FCC for Concerto listing me as an author though I asked that my name be removed from the report. • Getting away with breaking the rules has led Medtronic to break the rules in design and production for the new long-range telemetry implants. • Allowing Medtronic to bend or break the rules has led to behavior that is not doing Medtronic or their patients any favors.
My Role at Medtronic • I was the focal point for developing the initial implant and programmer production test plans. • I acquiesced to management pressure to produce a substandard plan which reduced testing over time. • I primarily defined and performed much of the engineering testing (EVT/DVT) on the D1C which was used to minimize Concerto testing. • I signed off on test plans that I knew to be inadequate. • I performed some of the Concerto testing.
Disavowal Until Medtronic provides evidence that they have evaluated the safety of the Concerto implant to a commercial high-reliability level, I disavow all work I have performed for Medtronic including all production related work, failure mode and effect analyses, worst case analyses, engineering verification tests, design verification tests (DVT), design reviews and all regulatory work, including all regulatory submittals. Sincerely, Christopher Fuller 8901 River Ridge Circle Bloomington, MN 55425 June 22, 2006