Sales of the second-generation Watchman FLX were suspended in Europe over unexpectedly high embolic event rates, Boston Scientific told investors Monday.
Patients with the left atrial appendage occlusion device — released in November in Europe, but not available on the U.S. market — showed unexpectedly high rates of embolism after implantation of 2.9% (six reports out of 207 implants). One of those patients died due to complications related to postoperative infection after the device was retrieved percutaneously.
With sales on hold, the company said it is searching for answers which may lie in physician training and implant technique.
An older-generation Watchman is in use domestically and was granted FDA approval in 2015. Trials are planned in the U.S. with the FLX device but not yet enrolling, according to ClinicalTrials.gov.
“This a device that is currently not available in the United States, so I don’t think there should be any fear for any of the patients who are receiving the current device in the United States,” Roxana Mehran, MD, of Icahn School of Medicine in New York, commented from the American College of Cardiology (ACC) 2016 Scientific Sessions.
Mehran expressed confidence that Boston Scientific will take appropriate measures to “do the right thing” for the affected European patients. “These types of things do happen in with device iterations,” she added, “so I don’t have any concerns.”
Gordon F. Tomaselli, MD, of Johns Hopkins, agreed.
The FLX marks “a new iteration of deployment,” Tomaselli said. “With any new technology, there are hiccups.”
“I don’t think pulling the FLX in Europe will make that much difference here,” he added in an interview. “Of course, anyone will be a little nervous, but I think this is a different technology, and I frankly don’t think it will affect the uptake here significantly … One of the reasons I say the standard Watchman uptake is not going to be hurt all that much, at least initially, is there is a lot of pent-up demand for this technology.”
Tomaselli concluded that “as long as the standard Watchman doesn’t start to have a bunch of post-marketing problems — and so far I haven’t heard of any — we probably won’t change what we do based on these findings.”