New technologies designed to prevent stroke by stopping clots in the heart’s left atrial appendage (LAA) from entering the bloodstream are attracting a surge of interest from medical device makers looking to expand the market for such treatments.
Medtech companies see the LAA closure market as ripe for rapid growth due to an increase in people with atrial fibrillation (AFib), an irregular heart rhythm that can raise the risk of stroke. The small pouch in the heart’s top left chamber is the source of more than 90% of embolic strokes in AFib patients that are not caused by a valve problem.
More than 37.5 million people worldwide are affected by AFib, and cases are projected to increase more than 60% by 2050 as the population ages, according to one estimate.
“It’s just a massive market, and it’s really underpenetrated,” said Needham & Co. analyst Mike Matson in an interview.
Boston Scientific, which leads the LAA closure market with its Watchman device, puts the current market at $1.4 billion and estimates that number could quadruple to more than $6 billion by 2030.
In AFib patients, the inefficient pumping of the heart can cause blood to pool and form clots within the LAA. Researchers have called it “the most lethal human attachment,” and its function is unclear. Because many people with AFib do not tolerate blood thinners well, a procedure-based treatment to close or eliminate the LAA offers another way to reduce stroke risk.
“A lot of patients are on blood thinners, but a lot of them have a high risk of bleeding, and they are seeking an alternative. And so, left atrial appendage closure is a good option for them,” said RBC Capital Markets analyst Shagun Singh.
Different approaches
The Watchman implant, delivered to the heart in a catheter-based procedure, fits into the LAA and is designed to permanently close it off to prevent clots from escaping and blocking blood flow to the brain.
More than 300,000 people have stopped taking oral anticoagulants after receiving a Watchman device, according to the company. Boston Scientific in September said it received U.S. approval for the latest generation of the implant, the Watchman FLX Pro, with a new size option and polymer coating to prevent device-related clots.
Abbott brought new competition to the market with the arrival of its Amplatzer Amulet device, approved by the Food and Drug Administration in 2021. Abbott’s device works similarly to Watchman, sealing off the LAA with a disc to prevent the need for blood thinners.
Reported net sales for Watchman grew year over year by 24% to $1.02 billion in fiscal year 2022, according to an earnings report from Boston Scientific. Meanwhile, Abbott said on an October earnings call that Amplatzer Amulet contributed to the company’s strong third-quarter device sales performance.
AtriCure makes the AtriClip, which is applied to the outside surface of the LAA by a cardiac surgeon, permanently closing the sac at its base to prevent blood from entering.
New market entrants
Medtronic and Johnson & Johnson are stepping up the competition with new techniques to address the AFib stroke risk associated with the LAA.
Medtronic last month revealed it acquired the Penditure LAA exclusion system in August from Miami-based medical device incubator Syntheon and is now launching the device in the U.S. market. The Penditure clip is implanted during related cardiac surgery procedures.
Analysts see Medtronic’s treatment as competing directly with AtriCure’s AtriClip, which was the only surgical LAA exclusion device on the U.S. market, according to Needham’s Matson.
Karim Bandali, president of Medtronic’s cardiac surgery business, has said the company estimates the left atrial appendage procedure market in the U.S. to be about $150 million.
“We will be very competitive to treat these patients with a differentiated surgical LAA solution,” he said last month in an email.
Days after Medtronic’s Penditure announcement, J&J said it acquired Laminar, a Santa Rosa, California-based company that is developing a new approach to eliminate the left atrial appendage. J&J paid $400 million upfront for Laminar, with potential for additional milestone payments, and expects to take a hit to its earnings per share in 2023 and 2024. Laminar has received FDA approval for a U.S. pivotal study of the device that will begin enrollment early next year.
“Current commercial catheter-based procedure devices use plugs to occlude the LAA. This approach may introduce procedure-related risks, including pericardial effusion (fluid build-up around the heart), peri-device leaks, device related thromboembolism, and device embolization,” J&J spokesperson Ryan Carbain said Monday in an email. “The Laminar novel approach uses rotational motion to completely close – or eliminate – the LAA.”
RBC’s Singh said the LAA market has room for the additional participants.
“I feel like everybody wins, because this is an area of unmet need,” said Singh.