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

Model Number	M635WU60350
Medical Device Problem Code	Failure to Seal (4070)
Health Effect - Clinical Code	No Clinical Signs, Symptoms or Conditions (4582)
Date of Event	09/02/2026
Type of Reportable Event	Serious Injury
Event or Problem Description
It was reported an implant did not seal.A left atrial appendage (laa) closure procedure was performed, and a 35mm watchman flx pro closure device was deployed.A 3 mm posterior/lateral peri-device leak at 0 degrees and a 2.5 mm posterior peri-device leak at 135 degrees were considered acceptable, and the device was released.The patient was discharged following the procedure.At a routine follow up, transesophageal echocardiography (tee) was performed, and it was noted the posterior peri-device leak had increased to 3.74 mm.As a result, the patient is unable to discontinue their prescribed blood thinner medication.

• 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: 50846219
• Report Number: 2124215-2026-50268
• Device Sequence Number: 10278498
• Product Code: NGV
• UDI-Device Identifier: 00191506004620
• UDI-Public: (01)00191506004620(17)281203(10)38111128
• 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: 2026
• Reporter Type: Manufacturer
• Report Source: Other,Foreign,Health Professional,Company Representative
• Initial Reporter Occupation: Physician
• Type of Report: Initial
• Report Date (Section B): 09/21/2026

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?: Yes
• Operator of Device: Health Professional
• Device Model Number: M635WU60350
• Device Catalogue Number: M635WU60350
• Device Lot Number: 0038111128
• 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: 09/17/2026
• Initial Report FDA Received Date: 09/21/2026
• Date Device Manufactured: 12/04/2025
• 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 Age: 78 YR
• Patient Sex: Male