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

Model Number	M635WU50310
Medical Device Problem Code	Adverse Event Without Identified Device or Use Problem (2993)
Health Effect - Clinical Code	Thrombosis/Thrombus (4440)
Date of Event	09/12/2025
Type of Reportable Event	Serious Injury
Event or Problem Description
It was reported that thrombosis occurred.A left atrial appendage closure procedure was performed and a 31mm watchman flx closure device was implanted.At the one (1) year routine follow up performed 403 days post index procedure, transesophageal echocardiography (tee) imaging revealed a small device related thrombus (drt) located on the face of the closure device.No medical intervention was performed.The patient is expected to fully recover.

• 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: 23368448
• Report Number: 2124215-2025-75747
• Device Sequence Number: 9950244
• Product Code: NGV
• UDI-Device Identifier: 08714729860518
• UDI-Public: (01)08714729860518(17)270215(10)33439241
• Combination Product (Y/N): N
• Initial Reporter State: MS
• 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: Health Professional,Company Representative
• Initial Reporter Occupation: Physician
• Type of Report: Initial
• Report Date (Section B): 10/23/2025

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: M635WU50310
• Device Catalogue Number: M635WU50310
• Device Lot Number: 0033439241
• 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: 10/17/2025
• Initial Report FDA Received Date: 10/23/2025
• Date Device Manufactured: 02/16/2024
• 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: 77 YR
• Patient Sex: Male
• Patient Weight: 91 KG