MRI Effects: SJM Confirm™ Implantable Cardiac Monitors

Effects of Magnetic Resonance Imaging (MRI) on SJM Confirm™ Implantable Cardiac Monitors

This letter is being provided in response to your request for information about Magnetic Resonance Imaging and SJM Confirm implantable cardiac monitors.

Background

Magnetic Resonance Imaging (MRI) is a medical imaging technique used in radiology to visualize detailed internal structures. It is important to note that the SJM ConfirmTM provides no therapy to the patient and is a cardiac diagnostic monitor only. It contains no lead wires.

Potential effects

SJM Confirm is Magnetic Resonance (MR) conditional. Patients can undergo MR scanning when following specific scanning conditions. In non-clinical testing, the MR conditional SJM Confirm™ produced a temperature rise of less than 3°C at a maximum MR system-reported whole body averaged specific absorption rate (SAR) of 3.9 W/kg as displayed on the MR scanner console for 60 minutes of MR scanning in a 1.5T closed bore MR scanner (manufacturer Phillips, model Intera 1.5, Software version: 9.5.2). Based upon this testing and the recommendations below St. Jude Medical does not anticipate any interference between MRI and SJM Confirm™ ICMs.

Recommendations

The following scanning conditions should be used:

  • Closed-bore, cylindrical magnet
  • Static magnetic field strength of 1.5 Tesla (1.5 T) only
  • Maximum gradient slew rate 200 T/m/s per axis
  • Whole body Specific Absorption Rate (SAR) less than or equal to 2.0 W/kg
  • The uninterrupted duration of active scanning (when radio frequency (RF) and gradients are on) over the chest during MRI must not exceed 60 minutes
  • Confirmation/absence of other contraindicated implantable devices and/or leads, including abandoned leads, lead extenders, and lead adaptors

If you have any questions on this topic, please contact St. Jude Medical CRM Technical Services.

PDF Effects of Magnetic Resonance Imaging (MRI) on SJM Confirm™ Implantable Cardiac Monitors (103kb)
Rev 12/15 US