Considering a LAA Occlusion Closure? Watch Out for Nickel Allergy
Approximately 8% of us have a nickel allergy. If you’ve had your ears pierced (or some other body part) and had to use “hypoallergenic” jewelry, you most likely have a nickel allergy. (My wife, Patti, says gold earrings also work for her nickel allergy but are more costly.) It is one of the most common causes of metal sensitivities in people. It’s estimated that 15% to 20% of women in the U.S. are allergic to nickel due to jewelry exposure.
If you’re one of the many A-Fib patients looking to close off their Left Atrial Appendage, be aware if you have a nickel allergy, you have limited choices of an occlusion device.
Thanks to Frances Koepnick for alerting us to this problem. She had to cancel having a Watchman implanted because of her nickel allergy.
Nickel in Occlusion Devices

Heart illustration showing the Left Atrial Appendage
Watchman occlusion device (Boston Scientific): The Watchman contains Nitinol, a metal that is approximately 50% nickel and 50% titanium. The manufacturer states that individuals with a nickel allergy are ineligible for a Watchman implant.
Amplatzer Amulet occlusion device (St. Jude Medical-Abbott): The Amulet also contains nitinol and, therefore, has the same implications for nickel allergy.
Hyper-sensitivity Diagnostic Test Results
Standard skin/patch testing is considered unreliable for metal allergy testing. “Metal-LLT (Lymphocyte Transformation Testing)” is a diagnostic test used by allergists to measure hypersensitivity responses.
Below is a sample of test results showing nickel sensitivity:
Metal Challenge | Stimulation Index | Range (percentile based) |
Aluminum | 0.9 | Normal (Non-Reactive) |
Nickel | 4.2 | Reactive |
Iron | 0.7 | Normal |
For LAA Closure: What To Do About a Nickel Allergy?
Right now Frances seems to have two options: the Lariat II device (SentraHEART Inc) and a surgical approach using the second generation AtriClip which does not contain nickel, and as such, is suitable for LAA closure in individuals with nickel allergies.
The Lariat II does contain Nitinol, but it is gold plated. The gold plating acts as a barrier to nitinol/nickel exposure. Though formerly approved by the FDA, the Lariat II device is currently in a second (extended) “Amaze”clinical trial which is due to be completed in December 2019. For more about the SentraHeart Lariat device, see my article, Lariat II Suture Delivery Device.
The AtriClip is traditionally used during open-heart, Maze, or Mini-Maze surgery to close off the LAA. But it can be used as a stand-alone secondary heart surgery, which is traumatic and risky. The first generation AtriClip is essentially a “rectangle” placed around the LAA. Then it’s collapsed to close off the LAA. It does contain nitinol (50% titanium + 50% nickel) to provide felxibility for insertion. One major advantage of the AtriClip is it removes (closes off) the LAA which also eliminates electrical activity (A-Fib signals) that the LAA may have been producing.
The second generation AtriClip is more like a “hair clip”. Once the clip is correctly placed around the LAA, it’s then “triggered” by a type of spring-loading which doesn’t require the flexibility of nitinol.
Additional warning: today’s pacemaker leads may also contain nickel.
Be very careful selecting a surgeon to install the AtriClip. As a stand-alone surgery, it can be somewhat challenging. Make sure your surgeon has a lot of experience and verifiable success results.