MRI SureScan Feature

The MRI SureScan™ feature permits a mode of operation that allows a patient with a SureScan system to undergo an MRI scan under the specified MRI conditions for use. A complete SureScan system is required for use in the MR environment. Medtronic offers a range of SureScan systems, consisting of a SureScan device and SureScan lead(s) for use in MR scanners operating at 1.5 or 1.5 and 3 Tesla(T). See the device list below.

Devices
MRI Tesla
1.5T and 3T
1.5T
 
Amplia MRI™ and Amplia MRI™ Quad
Revo™ MRI
 
Compia MRI™ Quad
 
 
Evera MRI™ XT DR
 
 
Evera MRI XT VR
 
 
Evera MRI S DR
 
 
Visia AF MRI™ VR
 
 
Advisa MRI DR™
 
 
Advisa MRI SR™ 
 
 
MicraTM Trans Catheter Pacing System (TPS)

 

 

A SureScan device must be paired with SureScan lead(s). Any other combination may result in a hazard to the patient during an MRI scan. Note that Micra TPS is a leadless pacing system and the previous statement does not apply. To verify that components are part of a SureScan system, visit www.mrisurescan.com.

SureScan symbol
MR Conditional symbol.  The Medtronic  SureScan system is MR Conditional and, as such, is designed to allow implanted patients the ability to undergo an MRI scan under the specified MRI conditions of use.

 

This feature can be found in some Medtronic Pacemaker, ICD, and CRT-D devices. Please go to manuals.medtronic.com or consult with your local Medtronic representative regarding device models available in your geography.

When programmed to On, MRI SureScan mode disables arrhythmia detection, therapies, Magnet mode, and all user-defined diagnostics. Before performing an MRI scan, refer to the SureScan pacing or defibrillator system MRI technical manuals for important information about procedures and MRI-specific warnings and precautions.

In transvenous pacemaker systems; to program MRI SureScan to On, go to Params -> Additional Features.

In the Micra Transcatheter Pacing System (TPS); to program MRI SureScan mode to On, go to the Parameters screen.

In ICDs and CRT-D devices, to program MRI SureScan mode to On, go to the Parameters Screen.
Or
Go to Params -> Pacing -> Additional Features.

Under the MRI SureScan field, the MRI SureScan Checklist appears as shown on the screen below. Read the checklist carefully as it may vary depending upon the device. Select the check box in the upper-left corner if all items on the MRI SureScan Checklist are satisfied for the patient. The MRI SureScan Checklist may be printed if desired.

Select OK at the bottom of the MRI SureScan Checklist and the MRI SureScan window appears. Programming MRI SureScan mode to On, allows for programming of an appropriate MRI SureScan pacing mode and MRI SureScan pacing rate as shown below. For patients who require pacing support, program the device to an asynchronous pacing mode (DOO, AOO, VOO for dual chamber (DR) devices and VOO for single chamber (SR) devices). A pacing rate must be selected for these pacing modes to avoid competitive pacing during the operation of MRI SureScan mode. For patients who do not require pacing support, program the device to the non-pacing mode (ODO for DR devices and OVO for SR devices) and a pacing rate is not required.

Transvenous pacemaker systems: MRI SureScan mode pacemaker programming screen

Micra TPS: MRI SureScan mode programming screen

On the Micra programming screen above, notice the Timeout indicator towards the top of the MRI SureScan page. The device automatically programs the MRI SureScan mode to Off after the indicated time (24 hours). The SureScan Timeout period of 24 hours ensures that the device will not remain in SureScan mode for an overly long period of time after the scan. However, once MR scanning is complete and the patient is in a safe area away from the magnet, interrogate the device and turn MRI SureScan mode to Off, to restore permanent settings.

MRI SureScan mode ICD programming screen

On the ICD programming screen above, and the CRT-D programming screen below, notice the Timeout indicator towards the top of the MRI SureScan page. In both ICD and CRT-D MRI systems, the device automatically programs the MRI SureScan mode to Off, 6 hours after it was programmed to On. This 6 hour timeout period is provided to protect the patient from prolonged exposure to spontaneous tachyarrhythmia. However, once MR scanning is complete and the patient is in a safe area away from the magnet, interrogate the device and turn MRI SureScan mode to Off, to restore permanent settings, detections and therapies, in order to ensure patient safety.

MRI SureScan mode CRT-D programming screen


Additionally, on the CRT-D programming screen above, notice that when MRI SureScan is programmed to On, V Pacing is RV only. Therefore, patients with a CRT-D device will not receive CRT support while MRI SureScan is programmed to On. This lack of CRT pacing may cause dizziness or shortness of breath. Be sure to program MRI SureScan to Off as soon as the MRI scan is complete.

When MRI SureScan mode is programmed to On, the message, "All Off" appears on the Device Status line, at the top of the programmer screen, to indicate that all detections and therapy features are suspended.

Considerations:

  • When MRI SureScan is programmed to On, the device does not do the following:
    • Detect atrial or ventricular tachyarrhythmias or PVCs
    • Deliver atrial or ventricular tachyarrhythmia therapies
    • Initiate asynchronous, fixed-rate bradycardia pacing in the presence of a magnet
  • When MRI SureScan is programmed to On:
    • All device diagnostic measurements, data collection and counters are suspended.
    • Bradyarrhythmia pacing therapy is provided when an asynchronous pacing mode (DOO, AOO, VOO) is selected for MRI SureScan operation.
    • When DOO mode is selected, the device automatically sets the PAV to either the permanently programmed PAV interval or 110 ms, whichever is less. However, if the permanently programmed PAV is less than 50 ms, the device automatically sets the PAV to 50 ms when MRI SureScan mode is programmed On.
    • When the pacing mode is DOO, AOO, or VOO, the device may automatically set the amplitude and pulse width values. If the permanently programmed RA Amplitude or RV Amplitude is less than 5.0 V, the amplitude is set to 5.0 V. If the permanently programmed RA Pulse Width or RV Pulse Width is less than 1.0 ms, the pulse width is set to 1.0 ms.
    • In transvenous pacemakers, if the battery voltage falls below the RRT, the normal RRT indication may not be displayed. If the feature is left on indefinitely, the patient will have no indication that the device has reached RRT.

A complete SureScan pacing, ICD or CRT-D system is required for use in the MRI environment. Any other combination may result in a hazard to the patient during an MRI scan. To verify that components are part of a SureScan system, visit www.mrisurescan.com. The SureScan feature must be programmed to On prior to scanning a patient according to the specified conditions for use.

Cardiology Requirements for Conventional Pacing, ICD and CRT Systems
Patients and their implanted systems must be screened to meet the following requirements:
  • SureScan transvenous pacing, ICD and CRT-D systems:
    • No implanted lead extenders, lead adaptors, or abandoned leads
    • No broken leads or leads with intermittent electrical contact, as confirmed by lead impedance history.
    • The SureScan system is implanted in the left or right pectoral region
    • For pacemaker-dependent patients, it is not recommended to perfomr an MRI scan if the right ventricular (RV) lead pacing capture threshold is greater than 2.0 V @ 0.4 ms. A higher pacing capture threshold may indicate an issue with the implanted lead.
    • The SureScan device is operating within the projected service life
    • No diaphragmatic stimulation is present at a pacing output of 5.0 V and a pulse width of 1.0 ms in patients whose device will be programmed to an asynchronous pacing mode when MRI SureScan is programmed On.
Note: It is not recommended to perfomr MRI scans during the lead materuation period (approximately 6 weeks).
  • Tranvenous Pacemaker specific requirements:
    • Pace polarity parameters set to Bipolar for programming MRI SureScan to On (Advisa MRI only).
    • Lead impedance value of ≥ 200 Ω and ≤ 1500 Ω.
    • Revo MRI patients must have pacing capture thresholds of ≤ 2.0 V at a pulse width of 0.4 ms and a SureScan pacing system that has been implanted for a minimum of 6 weeks.
Cardiology Requirements for the Micra TPS
Patients and their implanted Micra pacemaker must be screened to meet the following requirements:
  • No abandoned leads are present.
  • For patients who have multiple MR Conditional devices present (including multiple Micras), the MR labeling conditions for all implanted devices are satisfied.
  • The Micra device providing therapy is operating within the projected service life.
  • Pacing amplitude is ≤ 4.5 V at the programmed pulse width.
  • No diaphragmatic stimulation is observed when MRI SureScan is programmed to On.
 
Radiology requirements for Transvenou Pacing, ICD and CRT Systems:
Revo MRI devices can only be scanned using 1.5T systems. Please refer to the device table above.
  • Horizontal field, cylindrical bore, clinical system for hydrogen proton imaging
  • Static magnetic field of one of the following strengths (See details in table below):
    • 1.5T
    • 3T
  • Maximum spatial gradient of ≤ 20 T/m (2000 Gauss/cm)
  • Gradient systems with maximum gradient slew rate performance per axis of ≤ 200 T/m/s
3T – MRI Radio Frequency (RF) Power
1.5T – MRI Radio Frequency (RF) Power
First Level Controlled Operating Mode or
Normal Operating Mode:
  • B1+RMS must be ≤ 2.8 μT when the isocenter (center of the MRI bore) is inferior to the C7 vertebra.
  • Scans can be performed without B1+RMS restriction when the isocenter is at or superior to the C7 vertebra (see Figure 1).
Normal Operating Mode
  • Whole body averaged specific absorption rate (SAR) must be ≤ 2.0 W/kg
  • Head SAR must be ≤ 3.2 W/kg
 
Figure 1: 3T Scan Location Requirements
 
Radiology Requirements for Micra TPS
 
Scanner type
Horizontal field, cylindrical bore, clinical system
Scanner characteristics
  • Hydrogen proton magnetic resonance imaging equipment with a static magnetic field of 1.5T or 3.0T and a maximum spatial gradient of ≤25T/m (2500 Gauss/cm)
  • Gradient system with maximum gradient slew rate performance per axis of ≤ 200 Tesla per meter per second (T/m/s)
Scanner operation
MRI radio frequency (RF) power. The whole body average specific absorption rate (SAR) must be ≤ 4.0 watts per kilogram (W/kg). The head SAR must be ≤ 3.2 W/kg.
 
Patient Monitoring Requirements for all Systems and Micra TPS:
  • For SureScan ICD/CRT-Ds – continuous patient monitoring is required while MRI SureScan mode is programmed to On. An external defibrillator must be immediately available while MRI SureScan mode is programmed On. 
  • For SureScan Pacing Systems and Micra TPS, proper patient monitoring must be provided during the MRI scan. An external defibrillator must be available nearby during the MRI scan. 
  • Proper patient monitoring includes visual and verbal contact with the patient, and monitoring heart rate using instrumentation such as pulse oximetry (plethysmography) or electrocardiography.
Training Requirements for all Systems and Micra TPS:
  • A health professional who has completed cardiology SureScan training must be present during the programming of the SureScan feature. 
  • A health professional who has completed radiology SureScan training must be present during the MRI scan.

Before performing an MRI scan, refer to the SureScan system MRI technical manuals for important information about procedures and MRI-specific warnings and precautions.

 

References

Sources: Advisa DR MRI™  SureScan™ and Advisa SR MRI™ Clinician Manual, Advisa DR MRI™ and Advisa SR MRI™ SureScan™ Technical Manual, Revo™ MRI SureScan™ Pacing System MRI Technical Manual, Micra™ MC1VR01 MRI Technical ManualEvera MRI™ SureScan™ DR Reference Manual, Evera MRI™ SureScan™ Defibrillation System MRI Technical Manual,Visia AF MRI™ SureScan™ Defibrillation System MRI Technical Manual, Amplia MRI™/Amplia MRI™Quad, Compia MRI™/Compia MRI™Quad CRT-D Reference Manual.

Additional resource: www.mrisurescan.com
This website provides checklists and list of facilities with staff who have gone through training.

This document is for the use of medical professionals only and not intended for patients or consumers. If you are a patient, please go to www.medtronic.com to access patient information on our products and therapies.

Products and therapies referenced in this document as well as the materials available for viewing and download are based on US approved products and conditions of use.

This document is provided for general educational purposes only and should not be considered the exclusive source for this type of information. At all times, it is the professional responsibility of the practitioner to exercise independent clinical judgment in a particular situation. Changes in a patient's disease and/or medications may alter the efficacy of a device's programmed parameters or related features and results may vary. The device functionality and programming described on this site are based on Medtronic products and can be referenced in the published device manuals.

Last updated: 
20 Jun 2016