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

Model Number	M635WU60400
Medical Device Problem Code	Device Dislodged or Dislocated (2923)
Health Effect - Clinical Codes	Low Blood Pressure/ Hypotension (1914); Unspecified Tissue Injury (4559)
Date of Event	01/22/2026
Type of Reportable Event	Serious Injury
Event or Problem Description
It was reported that device embolization occurred.A left atrial appendage (laa) closure procedure was performed in a laa of broccoli morphology and a 40mm watchman flx pro closure device was implanted after meeting release criteria.Prior to discharge, during routine follow-up echocardiogram, the closure device was observed to have embolized into the left atrium and mitral valve.The physician attempted to remove the closure device percutaneously using a non-boston scientific grasping device and was able to grab the closure device but was unable to collapse the closure device to pull through the inner atrial septum.The patient was transferred to surgery and the 40mm watchman flx pro closure device was excised from the atrial septum and the inner atrial septum was repaired.Additionally, the laa was ligated via atriclip.During the event the patient experienced symptoms of hypotension and a very short duration of pulseless electrical activity.The patient is recovering in the intensive care unit but is reported to be doing well from a cardiac standpoint.The physician suspected the cause of the embolization to be related to the closure device being oversized, too proximal, and distally over-compressed, not seen by fluoroscopy imaging.
Event or Problem Description
It was reported that device embolization occurred.A left atrial appendage (laa) closure procedure was performed in a laa of broccoli morphology and a 40mm watchman flx pro closure device was implanted after meeting release criteria.Prior to discharge, during routine follow-up echocardiogram, the closure device was observed to have embolized into the left atrium and mitral valve.The physician attempted to remove the closure device percutaneously using a non-boston scientific grasping device and was able to grab the closure device but was unable to collapse the closure device to pull through the inner atrial septum.The patient was transferred to surgery and the 40mm watchman flx pro closure device was excised from the atrial septum and the inner atrial septum was repaired.Additionally, the laa was ligated via atriclip.During the event the patient experienced symptoms of hypotension and a very short duration of pulseless electrical activity.The patient is recovering in the intensive care unit but is reported to be doing well from a cardiac standpoint.The physician suspected the cause of the embolization to be related to the closure device being oversized, too proximal, and distally over-compressed, not seen by fluoroscopy imaging.
Additional Manufacturer Narrative
With all the available information, boston scientific (bsc) concludes: device technical analysis: the watchman flx? pro was discarded; therefore, returned device analysis could not be completed.Device history record review: a review was completed of the device history records (dhr) for the watchman flx? pro, part # m635wu60400, batch # 0037012677.The device was processed through all normal operational conditions and passed all acceptance activities.The dhr review did not identify any deviations or non-conformances that could have contributed to the event.Labeling review: there was evidence to suggest that the device was used in a manner inconsistent with the labeling.Watchman flx? pro instructions for use (ifu) lists potential complications, risks and adverse events that may be associated with the use of this device which include embolization (additional device required), device explant, valvular/vascular damage (tissue damage), and hypotension (intensive care, hospitalization).Risk review: a risk review was completed and confirmed that the events of embolization, device explant, valvular/vascular damage (tissue damage), and hypotension were defined in the risk documentation.These event types have been accounted for during product risk analysis to support acceptable risk benefit for the product.Investigation conclusion: based on a thorough review of the reported complaint, boston scientific has assigned an investigation conclusion code of failure to follow instructions.

• 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 ; EI
• Manufacturer Contact: rachel shields ; 4100 hamline ave n; arden hills, MN 55112 ; 6512422111
• MDR Report Key: 24258420
• Report Number: 2124215-2026-06340
• Device Sequence Number: 13173995
• Product Code: NGV
• UDI-Device Identifier: 00191506004637
• UDI-Public: (01)00191506004637(17)280719(10)37012677
• Combination Product (Y/N): N
• Initial Reporter State: ID
• Initial Reporter Country: US
• PMA/510(K) Number: P130013
• Number of Events Summarized: 1
• Summary Report (Y/N): N
• Device Implanted Year: 2026
• Device Explanted Year: 2026
• 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): 04/02/2026

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: M635WU60400
• Device Catalogue Number: M635WU60400
• Device Lot Number: 0037012677
• 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: 01/22/2026
• Supplement Date Received by Manufacturer: 03/27/2026
• Initial Report FDA Received Date: 02/04/2026
• Supplement Report FDA Received Date: 04/02/2026
• Date Device Manufactured: 07/20/2025
• 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: Hospitalization; Required Intervention
• Patient Age: 77 YR
• Patient Sex: Male
• Patient Race: White