MRI Safety for Patients with Mitral Valve Clips
Patients with mitral valve clips can safely undergo MRA of the carotid arteries as these devices are MRI-compatible. 1
Safety Considerations for MRI in Patients with MitraClip
The MitraClip device, which is used for transcatheter mitral valve repair (TMVr) in patients with mitral regurgitation, has been specifically approved for cardiac magnetic resonance imaging (MRI). A systematic analysis has demonstrated that cardiac MRI is both feasible and robust in patients who have undergone MitraClip procedures 1.
What to Expect During MRI:
- A small extinction artifact is typically observed around the clip during MRI
- This artifact does not interfere with the evaluation of cardiac morphology and function
- 1.5 Tesla MRI systems have been validated for use in these patients
Clinical Applications
MRI can actually be beneficial for patients with MitraClip as it allows for:
- Assessment of left ventricular dimensions and function
- Evaluation of mitral annulus diameter
- Measurement of left atrial size
- Monitoring of reverse cardiac remodeling after successful MitraClip placement
MitraClip Device Characteristics
The MitraClip is a polyester fabric-covered cobalt-chromium implant that creates a tissue bridge between the mitral leaflets 2. It functions by:
- Anchoring flail and/or prolapsed leaflets in degenerative MR
- Improving coaptation of tethered leaflets in functional MR
- Creating a double orifice mitral valve
Patient Selection for MitraClip
While not directly related to MRI safety, it's important to note that MitraClip is indicated for:
- Patients with severe (3+ or 4+) primary degenerative mitral regurgitation who are at prohibitive surgical risk 3
- Patients with severe secondary mitral regurgitation who remain symptomatic despite optimal medical therapy with LVEF 20-50% and LV end-systolic diameter <70 mm 3
Procedural Considerations
The MitraClip procedure is typically performed:
- Under general anesthesia
- Using an antegrade (transseptal) approach
- With transesophageal echocardiography (TEE) guidance
- Often requiring placement of 1-2 clips (though up to 4 may be used in some cases) 4
Clinical Outcomes
Successful MitraClip placement has been shown to result in:
- Reduced mitral regurgitation
- Improved functional capacity
- Positive cardiac remodeling that can be monitored with MRI 1
Conclusion for Clinical Practice
When considering MRA of the carotid arteries in patients with MitraClip:
- No special precautions are needed beyond standard MRI safety protocols
- The MitraClip device is MRI-compatible and does not pose a safety risk
- The small artifact around the clip does not significantly interfere with carotid imaging
- MRI can provide valuable information about both the carotid arteries and cardiac status
This guidance is supported by clinical evidence showing that cardiac MRI is safe and effective in patients with MitraClip devices 1.