MAUDE Adverse Event Report: BOSTON SCIENTIFIC CORPORATION WATCHMAN FLX? Pro; system, appendage closure, left atrial

Model Number	M635WU60400
Medical Device Problem Code	Off-Label Use (1494)
Health Effect - Clinical Codes	Bradycardia (1751); Non specific EKG/ECG Changes (1817); Low Blood Pressure/ Hypotension (1914)
Date of Event	05/06/2026
Type of Reportable Event	Death
Event or Problem Description
It was reported patient death occurred.A patient with a previously implanted watchman device (implanted in 2020) was found to have a thrombus in the left atrium and was scheduled for a thrombectomy procedure.During the procedure, the physician utilized a watchman trusteer access system (was), a 40 mm watchman flx pro laa closure device and delivery system (wds), and a flow runner aspiration system for thrombus removal.The physician intended to use the watchman flx pro closure device off label as a filter in the aortic arch.During the course of the procedure, the thrombus was dislodged and migrated from the left atrium, with the watchman flx pro closure device capturing it within the aorta while functioning off label as a filter.The thrombus was observed to suddenly dislodge from the watchman flx pro closure device and was no longer visualized.Immediately following this, the patient developed st segment elevation along with a decline in blood pressure and heart rate.Chest compressions were initiated, however, despite resuscitative efforts, the patient died.
Event or Problem Description
It was reported patient death occurred.A patient with a previously implanted watchman device (implanted in 2020) was found to have a thrombus in the left atrium and was scheduled for a thrombectomy procedure.During the procedure, the physician utilized a watchman trusteer access system (was), a 40 mm watchman flx pro laa closure device and delivery system (wds), and a flow runner aspiration system for thrombus removal.The physician intended to use the watchman flx pro closure device off label as a filter in the aortic arch.During the course of the procedure, the thrombus was dislodged and migrated from the left atrium, with the watchman flx pro closure device capturing it within the aorta while functioning off label as a filter.The thrombus was observed to suddenly dislodge from the watchman flx pro closure device and was no longer visualized.Immediately following this, the patient developed st segment elevation along with a decline in blood pressure and heart rate.Chest compressions were initiated, however, despite resuscitative efforts, the patient died.
Additional Manufacturer Narrative
With all the available information, boston scientific (bsc) concludes: device technical analysis the watchman flx? pro was discarded; therefore, returned device analysis could not be completed.Device history record review a review was completed of the device history records (dhr) for the watchman flx? pro, part # m635wu60400 batch # 0037809559.The device was processed through all normal operational conditions and passed all acceptance activities.The dhr review did not identify any deviations or non-conformances that could have contributed to the event.Labeling review there was evidence to suggest that the device was used in a manner inconsistent with the labeling.Intended use/indications for use: watchman flx pro is intended for percutaneous, transcatheter closure of the left atrial appendage.Watchman flx? pro instructions for use (ifu) lists potential complications, risks and adverse events that may be associated with the use of this device which include user used incorrect product for intended use, hypotension, arrhythmia (st segment elevation, bradycardia) and death (resuscitation).Risk review a risk review was completed and confirmed that the events of off label use, hypotension, arrhythmia (st segment elevation, bradycardia) and death were defined in the risk documentation.These event types have been accounted for during product risk analysis to support acceptable risk benefit for the product.Investigation conclusion based on a thorough review of the reported complaint, boston scientific has assigned an investigation conclusion code of cause traced to intentional off-label, unapproved, or contraindicated use.

• Brand Name: WATCHMAN FLX? Pro
• Common Device Name: system, appendage closure, left atrial
• Manufacturer (Section D): BOSTON SCIENTIFIC CORPORATION; 300 boston scientific way; marlborough MA 01752
• Manufacturer (Section G): Boston Scientific Corporation; ballybrit business park; galway ; EI
• Manufacturer Contact: rachel shields ; 4100 hamline ave n; arden hills, MN 55112 ; +1(651)242-2111
• MDR Report Key: 25222678
• Report Number: 2124215-2026-27010
• Device Sequence Number: 21276761
• Product Code: NGV
• UDI-Device Identifier: 00191506004637
• UDI-Public: (01)00191506004637(17)281027(10)37809559
• Combination Product (Y/N): N
• Initial Reporter State: KS
• Initial Reporter Country: US
• PMA/510(K) Number: P130013
• Number of Events Summarized: 1
• Summary Report (Y/N): N
• Reporter Type: Manufacturer
• Report Source: Health Professional,Company Representative
• Initial Reporter Occupation: Physician
• Type of Report: Initial,Followup
• Report Date (Section B): 07/27/2026

1 Device was Involved in the Event

1 Patient was Involved in the Event

• Is this an Adverse Event Report?: Yes
• Is this a Product Problem Report?: No
• Operator of Device: Health Professional
• Device Model Number: M635WU60400
• Device Catalogue Number: M635WU60400
• Device Lot Number: 0037809559
• Was Device Available for Evaluation?: No
• Is the Reporter a Health Professional?: Yes
• Was the Report Sent to FDA?: No
• Type of Report(Section G): Thirty-Day
• Initial Date Received by Manufacturer: 05/06/2026
• Supplement Date Received by Manufacturer: 07/23/2026
• Initial Report FDA Received Date: 05/19/2026
• Supplement Report FDA Received Date: 07/27/2026
• Date Device Manufactured: 10/28/2025
• Is the Device Labeled for Single Use? (Y/N): Yes
• Is This a Single-Use Device that was Reprocessed and Reused on a Patient? (Y/N): No
• Usage of Device: Initial
• Patient Sequence Number: 1
• Outcome Attributed to Adverse Event: Required Intervention; Death
• Patient Age: 80 YR
• Patient Sex: Male