The US Food and Drug Administration (FDA) is informing healthcare providers of potential differences in procedural outcomes between men and women undergoing transcatheter left atrial appendage occlusion (LAAO).
The agency said it is evaluating a real-world study, published in JAMA Cardiology, of 49,357 patients in the National Cardiovascular Data Registry LAAO Registry that suggested women might be at greater risk than men for procedural outcomes, including major adverse events after device implant.
“The FDA recognizes the limitations of these data, including that the study was not randomized, only included one LAAO device (the first-generation Watchman device), and did not include longer-term outcomes beyond in-hospital events. However, the analysis provides results from a large registry of patients treated with LAAO implants in the U.S.,” the agency said in its letter to healthcare providers today.
As reported last month, the study by Darden et al showed a significantly higher rate of adverse procedural events in women than in men, including any adverse events (6.3% vs 3.9%; P < .001), any major adverse events (4.1% vs 2.0%; P < .001), and hospital stay longer than 1 day (16.0% vs 11.6%; P < .001). Procedure-associated death was 0.3% in women and 0.1% in men.
The agency noted that the number of patients in the LAAO Registry analysis was much larger than the number of patients in the premarket studies of the Watchman device that supported its approval and in the premarket studies for the other approved LAAO devices.
LAAO devices are indicated to reduce the risk for thromboembolism from the LAA in patients with nonvalvular atrial fibrillation who are not good candidates for long-term anticoagulation. LAAO devices currently marketed in the United States are Boston Scientific’s Watchman and Watchman FLX devices and Abbott Medical’s Amplatzer Amulet device.
“Currently, the FDA believes the benefits continue to outweigh the risks for approved LAAO devices when used in accordance with their instructions for use,” the letter states.
The FDA will work with device manufacturers to evaluate the potential issue, including a review of available premarket and postapproval study data and other available real-world, postmarket datasets, the letter notes.
The agency will also work with device manufacturers, investigators, and the LAAO Registry to try to identify the causes of procedural outcome differences between women and men.
In the letter, the FDA recommends healthcare providers continue monitoring patients who have been treated with LAAO devices in accordance with the current standard of care. They should also discuss the risks and benefits of all available options for stroke prevention in patients with atrial fibrillation as part of shared clinical decision-making.
Any adverse events or suspected adverse events experienced by patients with LAAO devices should also be reported to the FDA through MedWatch, its adverse-event reporting program.