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 Code	Thrombosis/Thrombus (4440)
Date of Event	07/30/2026
Type of Reportable Event	Serious Injury
Event or Problem Description
It was reported thrombosis occurred.A left atrial appendage (laa) closure procedure was being performed, and a 31mm watchman flx pro laa closure device was implanted.The patient was discharged.At the patients routine 45-day follow-up transesophageal echocardiography (tee), a pedunculated, mobile, device related thrombus (drt) was observed on the watchman flx pro closure device.As a result, the patient remains on their oral anticoagulant medication.
Additional Manufacturer Narrative
B3 date of event: aware date was used as event date as actual event date was not known.

• 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: 50508443
• Report Number: 2124215-2026-46134
• Device Sequence Number: 21385329
• Product Code: NGV
• UDI-Device Identifier: 00191506004613
• UDI-Public: (01)00191506004613(17)281128(10)38071709
• Combination Product (Y/N): N
• Initial Reporter State: FL
• Initial Reporter Country: US
• PMA/510(K) Number: P130013
• Number of Events Summarized: 1
• Summary Report (Y/N): N
• Device Implanted Year: 2026
• Reporter Type: Manufacturer
• Report Source: Health Professional,Company Representative
• Initial Reporter Occupation: Physician
• Type of Report: Initial,Followup
• Report Date (Section B): 10/01/2026

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: 0038071709
• 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: 07/30/2026
• Supplement Date Received by Manufacturer: 09/30/2026
• Initial Report FDA Received Date: 08/28/2026
• Supplement Report FDA Received Date: 10/01/2026
• Date Device Manufactured: 11/29/2025
• 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; Other
• Patient Sex: Female