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

Model Number	M635WU50270
Medical Device Problem Code	Adverse Event Without Identified Device or Use Problem (2993)
Health Effect - Clinical Code	Thrombosis/Thrombus (4440)
Date of Event	07/11/2025
Type of Reportable Event	Serious Injury
Event or Problem Description
It was reported that thrombosis occurred.A left atrial appendage (laa) closure procedure was performed and a 27mm watchman flx closure device was successfully implanted in 2023.The patient was discharged.In (b)(6) 2025, the patient was scheduled for an atrial fibrillation ablation.After intubation, a transesophageal echocardiogram (tee) showed a thrombus on the closure device, and the procedure was therefore canceled.There were no patient complications.
Additional Manufacturer Narrative
D6a implant date: estimated as (b)(6) 2023 as implant date was noted as 2023.
Event or Problem Description
It was reported that thrombosis occurred.A left atrial appendage (laa) closure procedure was performed and a 27mm watchman flx closure device was successfully implanted in 2023.The patient was discharged.In (b)(6) 2025, the patient was scheduled for an atrial fibrillation ablation.After intubation, a transesophageal echocardiogram (tee) showed a thrombus on the closure device, and the procedure was therefore canceled.There were no patient complications.It was further reported that the patient was on xarelto before closure device implantation and following closure device implantation the patient was on aspirin only.Anticoagulation therapy was initiated as a treatment after the thrombus was discovered.
Additional Manufacturer Narrative
B5 describe event or problem: updated with additional information received.H6: impact code updated from f26 no health consequences or impact to f2303 medication required.

• 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: 22588637
• Report Number: 2124215-2025-49618
• Device Sequence Number: 21077684
• Product Code: NGV
• UDI-Device Identifier: 08714729860501
• UDI-Public: (01)08714729860501(17)250720(10)29803681
• 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: 2023
• Serviced by Third Party (Y/N): Unknown
• Reporter Type: Manufacturer
• Report Source: Health Professional,Company Representative
• Initial Reporter Occupation: Physician
• Type of Report: Initial,Followup
• Report Date (Section B): 08/04/2025

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 Expiration Date: 07/20/2025
• Device Model Number: M635WU50270
• Device Catalogue Number: M635WU50270
• Device Lot Number: 0029803681
• 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: 07/11/2025
• Supplement Date Received by Manufacturer: 07/31/2025
• Initial Report FDA Received Date: 07/24/2025
• Supplement Report FDA Received Date: 08/04/2025
• Date Device Manufactured: 07/21/2022
• 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: 78 YR
• Patient Sex: Female