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

Model Number	M635WU50200
Medical Device Problem Code	Adverse Event Without Identified Device or Use Problem (2993)
Health Effect - Clinical Codes	Stroke/CVA (1770); Muscle Weakness/Atrophy (1967); Speech Disorder (4415); Facial Paralysis (4585)
Date of Event	10/03/2024
Type of Reportable Event	Serious Injury
Event or Problem Description
Reported via clinical study.It was reported an embolic stroke occurred.A left atrial appendage (laa) closure procedure was performed on (b)(6) 2022, and a 20mm watchman flx closure device was implanted with complete laa seal and deployed device diameter of 18.0 mm.The patient was discharged the same day on apixaban (10 mg/day) and aspirin (81mg/ day).On (b)(6) 2024 (783 days post-index procedure), the patient presented to the emergency room (er) after experiencing sudden left-sided weakness, facial droop, and involuntary arm movement while standing.Symptoms resolved within 60-90 seconds but briefly recurred en route to the hospital.The patient also reported slurred speech and word-finding difficulty.Review of systems was positive for facial asymmetry, speech difficulty, and weakness.Physical and neurological exams were unremarkable.Ekg showed normal sinus rhythm with left bundle branch block.Computed tomography (ct) head showed no acute findings but noted chronic changes and left frontal encephalomalacia.Ct angiogram revealed no large vessel occlusion or aneurysm, with moderate atherosclerosis.Magnetic resonance imaging (mri) visualase brain ablation showed a right cerebellar lesion without significant edema.Aspirin was discontinued and apixaban initiated.The patient was hospitalized for further evaluation.On (b)(6) 2024, a stroke alert neurology consult was conducted.Ct head remained negative for acute changes.Mri brain revealed small acute infarcts in bilateral posterior frontal lobes, chronic small vessel ischemic changes, and right cerebellar encephalomalacia.Ct chest showed no acute pathology but noted a cardiac device, calcified granuloma, and coronary atherosclerosis.The patient was discharged home with outpatient neurology and primary care follow-up.On (b)(6) 2024, follow-up imaging prompted referral to neuroradiology for further evaluation of the cerebellar lesion.On (b)(6) 2024, neurology consultation concluded the event was likely cardioembolic, affecting bilateral middle cerebral artery (mca) territories.The patient was clinically stable with no new findings.On (b)(6) 2025, the patient returned for neurosurgical evaluation of the cerebellar lesion.The patient remained clinically stable with no concerning symptoms.Mri showed interval growth of the right cerebellar mass with increased enhancement.No other masses were found.Ct chest/abdomen/pelvis showed no primary lesion.The patient was referred for craniotomy workup and outpatient radiation oncology.On (b)(6) 2025, the patient underwent successful craniotomy for cerebellar mass and was discharged home (b)(6) 2025.

• 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 ; EI
• Manufacturer Contact: rachel shields ; 4100 hamline ave n; arden hills, MN 55112 ; 6512422111
• MDR Report Key: 22700216
• Report Number: 2124215-2025-53466
• Device Sequence Number: 9011330
• Product Code: NGV
• UDI-Device Identifier: 08714729860488
• UDI-Public: (01)08714729860488(17)250412(10)29222740
• Combination Product (Y/N): N
• Initial Reporter State: IA
• Initial Reporter Country: US
• PMA/510(K) Number: P130013
• Number of Events Summarized: 1
• Summary Report (Y/N): N
• Device Implanted Year: 2022
• Serviced by Third Party (Y/N): Unknown
• Reporter Type: Manufacturer
• Report Source: Study,Health Professional
• Initial Reporter Occupation: Physician
• Type of Report: Initial
• Report Date (Section B): 08/04/2025

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 Expiration Date: 04/12/2025
• Device Model Number: M635WU50200
• Device Catalogue Number: M635WU50200
• Device Lot Number: 0029222740
• 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: 07/16/2025
• Initial Report FDA Received Date: 08/04/2025
• Date Device Manufactured: 04/13/2022
• 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; Hospitalization
• Patient Age: 77 YR
• Patient Sex: Male
• Patient Race: White