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

Model Number	M635WU60400
Medical Device Problem Code	Adverse Event Without Identified Device or Use Problem (2993)
Health Effect - Clinical Codes	Stroke/CVA (1770); Thromboembolism (2654)
Date of Event	07/08/2025
Type of Reportable Event	Serious Injury
Additional Manufacturer Narrative
Literature citation: winner, m.Et al.(2025).Mechanism of stroke related to a small peridevice leak coupled with "reverse" device-related thrombus.Jacc: clinical electrophysiology.11(11).B3: bsc aware date used as event date as it is unknown.D4: detailed product information was not provided to bsc.Based on the nature of the information provided to bsc, it is not possible to perform a good faith effort to obtain additional information.Because the product is unknown at this time, we are unable to provide the complete unique identifier (udi) # and other product specific information.If additional details become available, a supplemental report will be submitted.
Event or Problem Description
Reported via literature article.It was reported that cerebral vascular accident (cva) occurred.A left atrial appendage (laa) closure procedure was performed and a 40mm watchman flx pro closure device was implanted under transesophageal echocardiogram (tee) guidance with approximately 22% compression and no peri-device leak noted at the time of implant.At 53 days post index procedure, follow-up computed tomography (ct) imaging demonstrated a peri-device leak (pdl) measuring approximately 2.2 mm with partial dense thrombosis noted on the appendage side of the closure device.The patient was transitioned to dual antiplatelet therapy in response to the event.At 297 days post index procedure, the patient presented with right-sided weakness and was diagnosed with an acute cva of ischemic origin, consistent with a cardioembolic source.Repeat tee demonstrated the pdl was unchanged in size with no thrombus on the atrial-facing surface of the closure device; however, partial thrombosis and a mobile thrombus were visualized on the appendage side of the closure device, adjacent to the pdl.In the physicians opinion the thrombus formation behind the closure device with embolization through the peri-device leak was the likely mechanism of the cva.

• 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: 23924842
• Report Number: 2124215-2025-93748
• Device Sequence Number: 21085750
• Product Code: NGV
• UDI-Device Identifier: 00191506004637
• UDI-Public: (01)00191506004637
• Combination Product (Y/N): N
• Initial Reporter State: OH
• Initial Reporter Country: US
• PMA/510(K) Number: P130013
• Number of Events Summarized: 1
• Summary Report (Y/N): N
• Serviced by Third Party (Y/N): Unknown
• Reporter Type: Manufacturer
• Report Source: Literature,Health Professional
• Initial Reporter Occupation: Physician
• Type of Report: Initial
• Report Date (Section B): 12/30/2025

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: M635WU60400
• Device Catalogue Number: M635WU60400
• 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: 12/25/2025
• Initial Report FDA Received Date: 12/30/2025
• 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
• Patient Age: 82 YR
• Patient Sex: Female