APPENDIX IV

Probability that a Sprint Fidelis Lead Fracture may Result in Critical Injury from Loss of Pacing

This appendix calculates the critical injury risk for a pacemaker dependent patient programmed according to Medtronic’s recommendations who experiences a Sprint Fidelis lead fracture. Based on currently available data, we estimate the critical injury risk to be less than 0.1% for the majority of pacemaker dependent patients through 30 months of implant time.

Probability of Sprint Fidelis lead fracture through 30 months of implant time:
2.5%

   

Proportion of fractures occurring in the anode or cathode conductors:
90%

  

Approximate percentage of patients without alert triggered prior to event:
51%*

   

Probability of an anode or cathode fracture resulting in a loss of pacing output:
6.9%

  

Overall probability of a Sprint Fidelis lead fracture occurring and resulting in a loss of pacing output:
0.08%

  

Not all pacemaker dependent patients experience critical injury with loss of pacing. We estimate this percentage to be 15%.

The resulting probability of a Sprint Fidelis lead fracture at 30 months resulting in critical injury due to loss of pacing is estimated to be approximately:
0.012%
(Conservatively, we conclude risk to be <0.1%)


*

This percentage may vary by implanted device.