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

Model Number	M635WU60240
Medical Device Problem Code	Adverse Event Without Identified Device or Use Problem (2993)
Health Effect - Clinical Codes	Low Blood Pressure/ Hypotension (1914); Pericardial Effusion (3271)
Date of Event	09/17/2026
Type of Reportable Event	Serious Injury
Event or Problem Description
It was reported that pericardial effusion occurred.A left atrial appendage closure (laac) procedure was performed and a 24mm watchman flx pro laa closure device and delivery system was implanted.Transesophageal echocardiography (tee) was used throughout the procedure and noted a physiological effusion prior to the procedure.The patient was noted to have an anterior chicken wing anatomy.The transeptal puncture (tsp) was completed and after one recapture the device was implanted.A post operative echo showed the effusion had grown.The patient blood pressure declined.A pericardiocentesis was performed and 200cc of red fluid was removed.The blood that was drained was transfused back into the patient.The patient has since been discharged home.

• 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: 50859027
• Report Number: 2124215-2026-50512
• Device Sequence Number: 9651649
• Product Code: NGV
• UDI-Device Identifier: 00191506004590
• 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
• Device Implanted Year: 2026
• Reporter Type: Manufacturer
• Report Source: Health Professional,Company Representative
• Initial Reporter Occupation: Other Health Care Professional
• Type of Report: Initial
• Report Date (Section B): 09/22/2026

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: M635WU60240
• Device Catalogue Number: M635WU60240
• Device Lot Number: 0039503090
• 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: 09/22/2026
• Date Device Manufactured: 06/04/2026
• 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 Sex: Unknown