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

Model Number	M635WU60310
Medical Device Problem Code	Adverse Event Without Identified Device or Use Problem (2993)
Health Effect - Clinical Codes	Non specific EKG/ECG Changes (1817); Thrombosis/Thrombus (4440)
Date of Event	09/11/2026
Type of Reportable Event	Serious Injury
Event or Problem Description
It was reported thrombosis occurred.A left atrial appendage closure (laac) procedure was being performed.A watchman access system (was) and a 31mm watchman flx pro laa closure device and delivery system (wds) was selected for use.The wds was advanced and deployed in the laa.After the fourth deployment, the transesophageal echocardiography (tee) imaging angles were being reviewed for positioning, and it was noticed that a thrombus was swirling in the distal end of the device/appendage.The physician was notified of the finding immediately, just as the notified certified registered nurse anesthetist (crna) reported electrocardiogram (ekg) changes (st elevation).The physician quickly got arterial access on the left femoral artery and wanted to immediately take the device out of the appendage.It was suggested that the device not be removed before we could confirm where the clot was.The thrombus was reported to have resolved approximately 12 minutes after the thrombus was first seen.The physician cancelled the procedure and decided to recapture the closure device and completely remove the devices out of the body.The patient woke with no cognitive deficits or movement issues.The physician plans to get a computed tomography (ct) scan at a later date and re-evaluate for a reattempt at implant.

• 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 H91 Y 868; EI H91 Y868
• Manufacturer Contact: mary crawford ; 4100 hamline ave n; arden hills, MN 55112 ; +1(651)440-0979
• MDR Report Key: 50793323
• Report Number: 2124215-2026-49507
• Device Sequence Number: 9570142
• Product Code: NGV
• UDI-Device Identifier: 00191506004613
• Combination Product (Y/N): N
• Initial Reporter State: TN
• 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
• Report Date (Section B): 09/16/2026

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: M635WU60310
• Device Catalogue Number: M635WU60310
• Device Lot Number: 0039031405
• Was Device Available for Evaluation?: No
• Is the Reporter a Health Professional?: Yes
• Type of Report(Section G): Thirty-Day
• Initial Date Received by Manufacturer: 09/11/2026
• Initial Report FDA Received Date: 09/16/2026
• Date Device Manufactured: 04/08/2026
• 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: Other
• Patient Age: 79 YR
• Patient Sex: Male
• Patient Weight: 200 LB