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 Codes	Stroke/CVA (1770); High Blood Pressure/ Hypertension (1908); Cognitive Changes (2551); Thrombosis/Thrombus (4440)
Date of Event	07/29/2026
Type of Reportable Event	Serious Injury
Event or Problem Description
It was reported thrombosis occurred.A left atrial appendage (laa) closure procedure was performed, and a 31mm watchman flx closure device was implanted on (b)(6) 2024.The patient was subsequently discharged.A physician later reported to a boston scientific (bsc) clinical specialist that the patient presented to a different hospital from the implanting facility on (b)(6) 2026, with an altered mental status.A transesophageal echocardiogram (tee) was performed and revealed the presence of a thrombus on the watchman flx closure device.The patient was placed on a stroke protocol for further evaluation and management.The patient underwent a computed tomography angiography (cta) of the head and neck, magnetic resonance imaging (mri) of the brain, and a transesophageal echocardiogram (tee) as part of the stroke evaluation.Findings were consistent with a percheron artery stroke and hypertensive urgency.An mri of the brain and brainstem without contrast performed on (b)(6) 2026, showed bilateral restricted diffusion within the thalami.The mri also noted prior infarctions involving the cerebellum and both cerebral hemispheres.The patient had not been compliant with keeping follow up appointments; therefore, a current medication regime could not be confirmed.The patient is currently in rehabilitation.

• 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 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: 50310189
• Report Number: 2124215-2026-44485
• Device Sequence Number: 8770487
• Product Code: NGV
• UDI-Device Identifier: 08714729860518
• UDI-Public: (01)08714729860518(17)270109(10)33182756
• Combination Product (Y/N): N
• Initial Reporter State: AL
• Initial Reporter Country: US
• PMA/510(K) Number: P130013
• Number of Events Summarized: 1
• Summary Report (Y/N): N
• Device Implanted Year: 2024
• Reporter Type: Manufacturer
• Report Source: Health Professional,Company Representative
• Initial Reporter Occupation: Physician
• Type of Report: Initial,Followup
• Report Date (Section B): 09/24/2026

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: M635WU50310
• Device Catalogue Number: M635WU50310
• Device Lot Number: 0033182756
• 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: 08/04/2026
• Supplement Date Received by Manufacturer: 09/23/2026
• Initial Report FDA Received Date: 08/18/2026
• Supplement Report FDA Received Date: 09/24/2026
• Date Device Manufactured: 01/10/2024
• 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: Hospitalization; Other
• Patient Age: 84 YR
• Patient Sex: Male