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

Model Number	M635WU60270
Medical Device Problem Code	Adverse Event Without Identified Device or Use Problem (2993)
Health Effect - Clinical Code	Thrombosis/Thrombus (4440)
Date of Event	09/14/2026
Type of Reportable Event	Serious Injury
Event or Problem Description
It was reported that device thrombosis occurred.A left atrial appendage (laa) closure procedure was performed, and a 27mm watchman flx pro closure device was implanted.The patient was discharged.At the one-year follow-up computed tomography (ct), findings of a device related thrombus (drt) extending beyond the fabric portion of the closure device were observed.The drt was layered from the screw portion toward the coumadin ridge side.Anticoagulant therapy had been discontinued three (3) months after the procedure, and the patient was currently taking antiplatelet medication.No infarction-like symptoms had been observed to date.After the ct findings were confirmed, anticoagulant therapy was resumed, and a follow-up ct was planned for 3 to 6 months later.
Additional Manufacturer Narrative
D6a implant date is an approximate date as the actual implant date is 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: 50915102
• Report Number: 2124215-2026-51384
• Device Sequence Number: 12094832
• Product Code: NGV
• UDI-Device Identifier: 00191506004606
• Combination Product (Y/N): N
• Initial Reporter Country: JA
• PMA/510(K) Number: P130013
• Number of Events Summarized: 1
• Summary Report (Y/N): N
• Device Implanted Year: 2025
• Reporter Type: Manufacturer
• Report Source: Other,Foreign,Health Professional,Company Representative
• Initial Reporter Occupation: Physician
• Type of Report: Initial
• Report Date (Section B): 09/28/2026

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: M635WU60270
• Device Catalogue Number: M635WU60270
• Device Lot Number: 0035186477
• 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: 09/14/2026
• Initial Report FDA Received Date: 09/28/2026
• Date Device Manufactured: 10/31/2024
• 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 Sex: Unknown