Michigan’s Leader in Implants to Reduce AFib-Related Stroke Risk
February 12, 2026When Noah Thormeier, DO, was beginning his fellowship in cardiology, a new implant device was making medical news for its ability to prevent stroke in certain patients with atrial fibrillation not caused by a heart valve problem.
As someone fascinated by the science of treating structural heart disease, Dr. Thormeier was paying attention. When he joined Trinity Health Medical Group, Cardiology - Muskegon a few years later as an interventional cardiologist, he set a goal: “To build a program where we could help our community and our region and provide that device to patients.”
That device is the WATCHMAN FLX™ PRO. And since launching the program in 2019, Dr. Thormeier has performed more of these procedures than anyone in Michigan. With 199 implants in 2025 alone, he likely will surpass a total of 1,000 procedures by the end of this year.
The motivation is simple for Dr. Thormeier.
“It is a huge value for patients who need it,” he said. “It's a pretty straightforward, simple procedure that gives them a huge benefit.”
Short procedure, quick recovery, lifetime benefits
Most often the procedure can be completed in 15 to 30 minutes, Dr. Thormeier said, and patients can usually go home about four hours later. They can resume their daily activities with limits on heavy lifting, he said. The biggest change in their life is that they have reduced their risk of stroke without having to take blood thinners.
Those anticoagulant medications often are prescribed to reduce the risk of stroke for people with atrial fibrillation (AFib), the most common type of heart arrythmia. AFib has been linked to a five-fold increase in risk of stroke, and the medications are used to reduce the formation of blood clots that could reach the brain. But blood thinners can carry their own risks.
Learn more about AFib: Understanding your irregular heartbeat — and how to treat it
Because you’re more than your irregular heartbeat, Trinity Health Michigan’s heart experts offer a wide range of sophisticated solutions — and one of those is the WATCHMAN.
“The issue is that, as we age, we all tend to have increased bleeding risks — nose bleeds, the bladder, colon issues, gastrointestinal, the list goes on,” Dr. Thormeier said. “Our gait and our balance become an issue. If you fall and hit your head while on a blood thinner, it's a much more significant event than if you're not on one.”
“What this device and this therapy has provided to people is the ability to still have stroke protection without having to get on and stay on those blood thinners,” he said.
‘Quite an amazing device’
When AFib disrupts the normal pumping action of the heart, blood can collect in a pouch on the side of the heart called the left atrial appendage. This causes stroke risk, because blood tends to clot when it doesn’t move.
The WATCHMAN device is used to close off the appendage in a procedure known as a Left Atrial Appendage Occlusion or Left Atrial Appendage Closure. This is a one-time procedure that, while not treating the AFib itself, reduces risk of stroke and eliminates the need for lifelong reliance on blood thinners.
“The device itself is quite amazing. When you show the device to patients, they say, ‘Well, how are you going to get this up into my heart?’” Dr. Thormeier said. “And the metal is so cool because it can be stretched out and you can take this device and stretch it out thin enough to go through the catheter to get into the appendage where you want to deliver the device. But the minute it's freed up, it goes into position in the shape it's designed to be.”
Once the implant is in place, heart tissue grows over it and permanently seals it.
Video: This Is the WATCHMAN Implant
How do patients become eligible for this procedure?
Every patient that undergoes the WATCHMAN procedure must be referred by another physician, and then they will be evaluated by Dr. Thormeier and his team. This includes confirming the patient has AFib not caused by a valve problem, and that there are reasons to avoid blood thinners.
“The majority of our patients have bleeding problems for various reasons,” he said. “People who have a history of falls are probably the second most common. And then there's also indications for lifestyle.”
That group could include people whose occupations or hobbies put them at risk of being cut and bleeding excessively.
“Somebody who uses chainsaws or somebody who works with sharp objects, people who like to mountain bike or do activities where you're at risk of falling,” he said.
Dr. Thormeier performs the procedure in Muskegon but draws patients from a large part of West Michigan and the Lakeshore communities.
“Our access is good and our time to procedure is the best in the state. The only real limiting factor to when a patient can get this done is how quickly their insurance can authorize the procedure,” he said. “There are patients I can see on a Thursday, and they could get their procedure next Wednesday. And a lot of that is just due to how great our team is here in Muskegon.”
Providing that expertise and access has been gratifying for Dr. Thormeier and his team, because the need is so great.
Read about Vicky, one of Dr. Thormeier’s patients: From AFib to freedom: How advanced heart procedures changed a patient’s life
“It's an amazing feeling. I'm very thankful for the career I chose and the job I get to do every day,” he said. “You just feel very fortunate that you can provide that to patients. And when you see them six months, a year down the road, you can see they are very thankful they had this procedure. You feel like you really helped somebody. That's mostly why you become a doctor.”