Cardiovascular Implantable Electronic Devices -> Monitoring & Outcomes: -> Quality Measures & Complications D-PO06 - Poster Session VI (ID 26) Poster

D-PO06-023 - Impact Of MR Exposure On VF Detection Time And Left Ventricular Lead Threshold In MR Conditional ICD/CRT-D Systems (ID 646)

 C.A. Henrikson: Nothing relevant to disclose.


Background: MR conditional ICD systems have been demonstrated to be safe with respect to MRI-related serious adverse device effects, including changes in right ventricular pacing threshold or R-wave sensing. However, the effects of MR exposure on VF detection in MR conditional ICD/CRT-D systems and left ventricular (LV) threshold in CRT-D systems have not been evaluated.
Objective: Assess VF detection delay and evaluate MRI induced LV pacing threshold changes post-MR exposure.
Methods: BIOTRONIK MR conditional ICD/CRT-D systems registered with Home Monitoring were retrospectively analyzed through a de-identified database. The database provided all transmitted lead electrical parameters, programming settings, dates of MRI mode activation, and IEGMs. MRI mode activations were considered evidence of MR exposure. IEGMs and programming settings of VF episodes detected after MR exposure were provided to an independent Clinical Events Committee (CEC) to determine if the event was true VF, and to assess if any delay in detection was attributable to the MR exposure. LV lead electrical parameters transmitted via remote monitoring were compared between pre-MR exposure and one-month post-MR exposure, with an increase of >1.0 V in capture threshold considered significant.
Results: Out of 24,249 MR conditional ICD/CRT-D systems followed for an average of 647.5 days, 1,208 experienced an MR exposure. A total of 145 device-detected VF events after MR exposure were adjudicated by the CEC with 106 episodes classified as true VF and 39 episodes as other, including fast VT, SVT, and AF with RVR. True VF episodes occurred in 45 unique ICD/CRT-D systems (40 ICD, 5 CRT-D). None of the adjudicated True VF episodes were determined to have a delay in VF detection. For the 92 subjects with available LV lead measurement data pre and post-MR exposure, the mean change was 0.03 V (SD: ±0.15 V; minimum: -0.2 V; maximum 1.0 V).
Conclusion: The results demonstrate appropriate post-MR exposure VF detection for BIOTRONIK MR conditional ICD/CRT-D systems, with no evidence of delay in VF episode detection following MR exposure with the use of an MRI mode. For CRT-D systems, LV thresholds were stable post-MR exposure, with no systems experiencing a threshold increase of ≥1.0V one-month post-MR exposure.