St. Jude Medical Tendril MRI LPA1200M, User Manual

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Secondary Endpoint Results
System-Related Complications
Nine hundred twenty (920) patients who had an Accent MRI
™ pacemaker system attempted or
successfully implanted were analyzed for this endpoint. Forty-five (45) system-related
complications (RA lead, RV lead, pacemaker- and system-related complications) were observed.
The probability of system-related, complication-free survival at the 12-month follow-up visit was
calculated as 94.64% with a 95% lower confidence bound of 92.76%, which is greater than the
objective performance criterion of 80%.
RA Lead Capture Threshold at the MRI Visit (pre-scan)
The proportion of patients who experienced a capture threshold of ≤2.0 V at 0.5 ms at the MRI
visit (pre-scan) was calculated as 100% with a 95% lower confidence bound of 97.69%, which is
greater than the objective performance criterion of 85%.
RV Lead Capture Threshold at the MRI Visit (pre-scan)
The proportion of patients who experienced a capture threshold of ≤2.0 V at 0.5 ms at the MRI
visit (pre-scan) was calculated as 100% with a 95% lower confidence bound of 97.98%, which is
greater than the objective performance criterion of 85%.
Additional Data
Patient Discontinuation/Withdrawals
A total of one hundred and five (105) patients participating in MRI Study were withdrawn from the
study. Two (2) patients were withdrawn approximately one month after unsuccessful system
implants in accordance with the protocol. Fifty-six (56) patients died and were also withdrawn
from the study. In addition to these two unsuccessful implants and 56 deaths, 47 additional
patients were withdrawn from the study. The table below summarizes the reason for all the patient
withdrawals.
Table 6. Patient withdrawals, including deaths and unsuccessful implants
Reason for Withdrawal # of Patients
Patient and/or Family Request 27
Patient Death 56
Patient Lost To Follow-Up 2
Patient Participation Terminated By Investigator 5
System Explanted Without A System Replacement 13
Unsuccessful Implant 2
Total 105
Conclusions Drawn from the Study
In patients indicated for implantation of a pacemaker, this study demonstrated that the
Accent MRI
™
pacemaker and Tendril MRI
™
lead is effective and can be safely scanned in an MRI
environment.
Conformance to Standards
The lead complies with IS-1 connector standard ISO 5841-3.