MRI contraindications

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MR Contraindications[1]

Cardiovascular Devices

Device MR Category Comments
Aortic stent grafts Most MR Safe Zenith AAA and TAA endovascular grafts (Cook) = MR Conditional
Cardiac closure and occluder devices Most MR Safe (some MR Conditional)
Coronary artery stents Most MR Safe (some MR Conditional) Check individual type
Embolization coils Most MR Safe (some MR Conditional)
Loop recorder (Event monitor) MR Conditional? Stored data may be affected
Mechanical cardiac valves Most MR Safe (some MR Conditional) Ie. prosthetic heart valves and annuloplasty rings
Sternal wires Generally considered MR safe
Hemodynamic monitoring and temporary pacing devices MR Unsafe
Hemodynamic support devices MR Unsafe I.e. Intraaortic balloon pump and ventricular assist devices
IVC filters Most MR Safe (some MR Conditional) Weakly ferromagnetic devices [e.g. Gianturco bird nest IVC filter (Cook), stainless steel Greenfield vena cava filter (Boston Scientific)]: after six weeks as long as no reason to suspect improper positioning or movement
Permanent pacemakers and ICDs Strong relative contraindication vs. MR Unsafe Absolute contraindication: pacemakers or ICDs with known lead fractures
Peripheral vascular stents Most MR Safe (some MR Conditional) Check individual type
Pulmonary artery monitoring/thermodilution catheters MR Unsafe (unless otherwise specified) I.e. Swan-Ganz catheter and similar catheters
Temporary pacemaker MR Unsafe I.e. External pulse generators or temporary pacing leads
Retained transvenous pacemaker and defibrillator leads Strong relative contraindication vs. MR Unsafe Approached same as those with pacemakers or ICDs (see above)

Permanent pacemakers and implantable ICDs

  • Only if no alternative diagnostic test is available and the potential benefit to the patient clearly outweighs the potential risks
  • If performed, the pacemaker/ICD should be interrogated before and after the procedure
  • Risks:
    • pacemaker/ICD dysfunction
    • pacemaker/ICD damage
    • arrhythmia
    • death

Non-Cardiovascular

Device MR Category Comments
Nerve stimulators MR Unsafe
Cochlear implants MR Unsafe
Aneurysm clips Ferromagnetic: MR Unsafe; Non/weakly-ferromagnetic: MR Safe Requires specific information about clip material
Dental materials (alloys, wires, splints, and prostheses) MR Safe
Neurosurgical halo pins MR unsafe?
Transdermal patches If contain aluminum or other metals (in non-adhesive backing): MR Unsafe Remove before MR. Examples include certain clonidine, nicotine, scopolamine, testosterone, or fentanyl patches
Unstable patient MR Conditional Probably should avoid unless an urgent clinical indication without acceptable alternative

Other

  • Pregnancy: Unknown (if any, probably low)
    • Gadolinium-based contrast not recommended unless benefit justifies risk (crosses the placenta)
  • Claustrophobia
  • Agitated
  • Very Obese (depending on system)

MR (Gadolinium-Based) Contrast[2]

Background

  • Unlike iodinated contrast, MR contrast has few side effects and rarely cause anaphylaxis
  • It does cross the placenta

Specific Groups

  • Pregnancy (see above)
    • Gadolinium-based contrast not recommended unless benefit justifies risk
  • Moderate to severe chronic kidney disease:
    • Contrast nephropathy can occur (contraindicated)
  • Dialysis and hepatorenal patients in the perioperative liver transplant period

Key

  • MR Safe: Generally safe
  • MR Conditional: Weigh risk/benefit (relative contraindication)
  • MR Unsafe: Generally contraindicated (absolute contraindication)

See Also

References

  1. 25.Levine GN, Gomes AS, Arai AE, et al. Safety of magnetic resonance imaging in patients with cardiovascular devices: an American Heart Association scientific statement from the Committee on Diagnostic and Interventional Cardiac Catheterization, Council on Clinical Cardiology, and the Council on Cardiovascular Radiology and Intervention: endorsed by the American College of Cardiology Foundation, the North American Society for Cardiac Imaging, and the Society for Cardiovascular Magnetic Resonance. Circulation 2007; 116:2878.
  2. 25.Levine GN, Gomes AS, Arai AE, et al. Safety of magnetic resonance imaging in patients with cardiovascular devices: an American Heart Association scientific statement from the Committee on Diagnostic and Interventional Cardiac Catheterization, Council on Clinical Cardiology, and the Council on Cardiovascular Radiology and Intervention: endorsed by the American College of Cardiology Foundation, the North American Society for Cardiac Imaging, and the Society for Cardiovascular Magnetic Resonance. Circulation 2007; 116:2878.