Expanded follow-up to the Amulet IDE trial also hinted at more hardware-related strokes with this earlier Watchman iteration.
Boston, MA – For patients with atrial fibrillation who are undergoing left atrial attachment (LAAO) obstruction, Amplatzer Amulet (Abbott) and first generation Watchman 2.5 devices (Boston Scientific) provide similar clinical outcomes for up to 3 years, as extended Follow up on the Amulet Investigation Device Exemption (IDE) experience.
The results reinforce what has been seen in first results At 18 months old, Dhanunjaya Lakkireddy, MD (Kansas City Heart Rhythm Institute and Research Center, Overland Park, KS) reported here at TCT 2022. Released last year, previous results showed that the Amplatzer Amulet was superior to the first generation Watchman device in terms of LAA shutdowns. at 45 days, and no less safe at 12 months and efficacy at 18 months. The trial was used to support US Food and Drug Administration approvalmaking the Amplatzer Amulet the second LAAO device available to US operators.
Now, in an extended follow-up that included patients for whom the transplant was attempted, “the double-seal mascot blocker has continued to demonstrate safety and efficacy within 3 years in the first large-scale, randomized clinical trial of LAAO,” Lakeriddi said at a press conference, noting that this is the The largest trial comparing two LAAO devices to date.
Furthermore, “the closure of the amulet provides immediate and permanent closure to reduce the risk of stroke,” said Lakeriddi. He added that at 18 months of age, the presence of a device leak of 3mm or more was approximately 10% with the amulet and 20% with the Watchman 2.5.
The message to the general population, he said, includes “confidence in the closure of the amulet to provide immediate and long-term closure so that patients can safely remove or walk away from oral anticoagulants.”
Commenting on TCTMD, Dharam Company, MD (UT Southwestern Medical Center, Dallas, TX), a member of the American College of Cardiology’s Interventional Division, noted that initial Amulet IDE results showed a higher upfront risk of complications related to the procedure with Amplatzer Amulet, but Fewer leaks surrounding the device. So it was important to see how this was done in terms of long-term clinical outcomes, he said, and in this regard, “at least clinically speaking, the devices look very similar.”
He noted that this experiment only evaluated the Watchman 2.5, not the newer Watchman FLX, so this is not a comparison to the more commonly used devices in current practice. Little Swiss Ibero However, the experiment compared the Amplatzer Amulet and Watchman FLX, and similarly showed that using the Amplatzer Amulet resulted in more procedural complications but fewer leaks surrounding the device, as described in the Amulet IDE.
But with similar clinical outcomes up to at least 3 years, Kompany said, “I think device choice is probably driven by patient and clinician factors.”
IDE Amulet in 3 years
The Amulet IDE trial initially randomized 1,878 patients at 78 centers in the United States and 30 elsewhere, including 1,833 (mean age approximately 75 years; about 60% of men) for whom transplant was attempted. Of these, 1,380 completed 3-year visits, with the largest follow-up in the Amplatzer Amulet arm. This imbalance was driven by a higher number of deaths and withdrawals in the sentinel arm during the first 18 months of the study, Lakeridde said.
Oral anticoagulant use was lower in patients treated with Amplatzer Amulet versus Watchman throughout the follow-up period, with significant differences at 6 months (2.8% versus 4.7%), 18 months (3.1% versus 5.6%), and 3 years. (3.7%). % vs 7.3%; s < 0.05 for all). That could be related to the higher incidence of device-related thrombus-related (DRT) in the Watchman group, Lackerde said, noting that more of these patients were placed on oral anticoagulants after setting late DRT compared with those treated with Amplatzer Amulet. (23 vs 10).
“This is something we have to watch out for,” said Lackerde. It was suggested that the difference in the DRT could be related to differences in hardware design, as the Amplatzer Amulet has a flat disc that provides a smooth surface covering the LAA nozzle.
Lakeridde suggested that the increase in DRT seen in the Watchman arm did not translate into worse clinical outcomes, possibly because any risks associated with DRT were mitigated by increased use of oral anticoagulants. There were no significant differences (s = NS for all) for any of the following events in 3 years when comparing the Amplatzer Amulet to the Watchman:
- Stroke, systemic embolism, or CV death (11.1% vs 12.7%)
- CV death (6.6% vs. 8.5%)
- Death from all causes (14.6% vs. 17.9%)
- Stroke or systemic embolism (5.0% vs. 4.6%)
- Heavy bleeding (16.1% vs. 14.7%)
The investigators found that device-related factors, particularly leakage surrounding the device, more commonly preceded CV death and stroke in the Watchman arm than the trial. “Pay attention should be paid to device selection and how we can mitigate the risk of device leakage surrounding these patients,” said Lackerde. pre-search showed an association between perioperative leaks after LAAO and poorer long-term outcomes.
Choose one device over another
Commenting on the findings at the press conference, Federico Asch, MD (MedStar Health Research Institute, Washington, DC), said, “The most exciting thing here is that we have good options. We can now begin to identify patients who will benefit best from one or the other.”
But Lakereddy said there are a few factors that might favor choosing the Amplatzer Amulet over the Watchman 2.5. Appendices with close lobes, large orifices, or shallow depths, for example, can be better handled with Amplatzer Amulet, while for other formulations, it’s a “fling” between the two devices, he said.
Lakereddy noted that it is not known whether the results observed in the Amulet IDE, which used a first generation Watchman, are generalizable to the newer Watchman FLX, which comes in a larger size and has been shown to perform better than the older occlusal device. Also, the Food and Drug Administration recently allowed the addition of Dual antiplatelet therapy as a postoperative option to the Watchman FLX poster; Until this month, a short period of anticoagulation was the recommended approach.
Right now, the usage patterns of the available LAAO device options are “mainly driven by your comfort with the device and the kind of experience you really have using these types of devices,” Lakereddy said.