Shortly after scoring an FDA approval for its Amplatzer Amulet structural heart device this month, Abbott delivered late-breaking clinical trial data putting it up against its main competitor, Boston Scientific’s Watchman implant.
Both minimally invasive devices are designed to reduce long-term stroke risks in patients with atrial fibrillation by permanently sealing off a small pocket within the heart wall known as the left atrial appendage, where blood can pool and form dangerous blood clots in people with an irregular heartbeat.
Watchman has sat uncontested in this market since Boston Scientific garnered an FDA approval in 2015, after years of regulatory setbacks and rejections. Now, Abbott hopes to quickly claim a large piece of the pie, as it has in Europe since Amulet’s 2013 CE mark and rollout.
With the latest head-to-head study data, presented today at the annual congress of the European Society of Cardiology, Abbott said its device led to more successful implantations and appendage closures.
Among more than 1,800 patients with an average age of 75, the Amplatzer Amulet was correctly placed in 98.4% of the one-time procedures compared to 96.4% with the Watchman device, leading to closures in 98.9% of cases compared to 96.8%, respectively.
The Amulet’s dual-seal design also helped overcome differences in patient anatomy, including shorter appendage lengths and varying sizes and shapes of the opening, according to a statement from the study’s principal investigator, Dhanunjaya Lakkireddy, M.D., of the Kansas City Heart Rhythm Institute.
While Boston Scientific’s version opens more like an umbrella to help fill the pouch, Abbott’s flattens into a mesh disc to block off the opening while expanding a separate shape to fill the inside of the appendage.
According to Abbott, this two-pronged approach allows the Amulet device to be used without requiring blood-thinning medications. Patients using the Watchman device, on the other hand, may need a drug regimen for at least three months after the procedure.
In the trial, 82% of Watchman patients were discharged with a prescription for anticoagulants, such as warfarin and aspirin, compared to 20% of Amulet patients—who were instead largely given a dual antiplatelet therapy regimen of clopidogrel and aspirin in 75% of cases.
The study found the Amulet performed as well as the Watchman when it came to safety and procedure-related complications—with similar rates of all-cause deaths and major bleeding after one year plus rates of stroke or embolism across 18 months.
“Atrial fibrillation cases have increased in recent years as the world continues to age, making stroke risk more prevalent and resulting in higher usage of blood-thinning medication that can lead to bleeding and other complications,” Lakkireddy said.
Earlier this year, Boston Scientific presented two-year Watchman study data showing steep cuts in stroke rates, with a drop of 77% among high-risk afib patients. The company is currently comparing the performance of the device to blood-thinning medications in patients who have undergone a cardiac ablation procedure.