MAUDE Adverse Event Report: BOSTON SCIENTIFIC CORPORATION WATCHMAN FLX?; SYSTEM, APPENDAGE CLOSURE, LEFT ATRIAL

Model Number	M635WU50240
Medical Device Problem Code	Adverse Event Without Identified Device or Use Problem (2993)
Health Effect - Clinical Codes	Pulmonary Embolism (1498); Dyspnea (1816); Thromboembolism (2654); Thrombosis/Thrombus (4440)
Date of Event	07/28/2025
Type of Reportable Event	Serious Injury
Additional Manufacturer Narrative
B3: bsc aware date used as event date, as it is unknown at the time of this report.
Event or Problem Description
The following event originated from a patient calling the watchman patient call center, and therefore despite good faith efforts the information is often incomplete.Additionally, due to the limited information received through good faith efforts, this event may represent a duplicate of an event which was already known to boston scientific.It was reported that thrombosis occurred.The patient was taking a blood thinner prior to the index procedure.A left atrial appendage (laa) closure procedure was performed and a 24mm watchman flx closure device was implanted.The patient was taking plavix and aspirin post index procedure, and then ultimately just aspirin.Approximately over (1) year post index procedure, the patient experienced shortness of breath and was hospitalized, and device related thrombus (drt) on the closure device, thrombosis in bilateral lower extremities, and thrombosis in the lungs were found.No further details were provided at the time of this report.

• Brand Name: WATCHMAN FLX?
• 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 ; 6512422111
• MDR Report Key: 22883652
• Report Number: 2124215-2025-59206
• Device Sequence Number: 8861366
• Product Code: NGV
• UDI-Device Identifier: 08714729860495
• UDI-Public: (01)08714729860495(17)261211(10)33041520
• Combination Product (Y/N): N
• Initial Reporter State: TX
• Initial Reporter Country: US
• PMA/510(K) Number: P130013
• Number of Events Summarized: 1
• Summary Report (Y/N): N
• Device Implanted Year: 2024
• Serviced by Third Party (Y/N): Unknown
• Reporter Type: Manufacturer
• Report Source: Consumer
• Initial Reporter Occupation: Other
• Type of Report: Initial
• Report Date (Section B): 08/25/2025

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: M635WU50240
• Device Catalogue Number: M635WU50240
• Device Lot Number: 0033041520
• Was Device Available for Evaluation?: No
• Type of Report(Section G): Thirty-Day
• Initial Date Received by Manufacturer: 07/28/2025
• Initial Report FDA Received Date: 08/25/2025
• Date Device Manufactured: 12/12/2023
• 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; Hospitalization
• Patient Age: 76 YR
• Patient Sex: Female