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

Model Number	M635WU60200
Medical Device Problem Code	Adverse Event Without Identified Device or Use Problem (2993)
Health Effect - Clinical Code	Pericardial Effusion (3271)
Date of Event	02/23/2026
Type of Reportable Event	Death
Event or Problem Description
It was reported that death occurred.A left atrial appendage (laa) closure procedure was being performed, and a 20mm watchman flx pro closure device and a watchman trusteer access system (was) were selected to be used.During the procedure, an attempt was made to implant the 20mm watchman flx pro closure device.After three attempts with low compression the physician tried the was sheath with a new 20mm watchman flx pro closure device while waiting for a non-boston scientific (bsc) closure device to arrive.With the was sheath, the physician was still not able to get the 20mm watchman flx pro closure device to have enough compression.The was sheath and the 20mm watchman flx pro closure device were removed from the left atrium and after about 20-30 minutes, the non-bsc closure device was available.The physician attempted with the original transseptal puncture but ended up having to re-stick.The non-bsc 18mm closure device was implanted.After the procedure, during the post-procedure echocardiography, the patient developed agonal breathing and began to decompensate.Chest compressions began.The physician attempted to place a drain bedside but was unable.The patient was transferred to the catheterization laboratory for a pericardiocentesis, but no blood or clot could be removed from the pericardial sac.A cardiac surgeon was brought in and performed a cardiac window.Clot was removed but the patient kept bleeding and passed away on the table.
Event or Problem Description
It was reported that death occurred.A left atrial appendage (laa) closure procedure was being performed, and a 20mm watchman flx pro closure device and a watchman trusteer access system (was) were selected to be used.During the procedure, an attempt was made to implant the 20mm watchman flx pro closure device.After three attempts with low compression the physician tried the was sheath with a new 20mm watchman flx pro closure device while waiting for a non-boston scientific (bsc) closure device to arrive.With the was sheath, the physician was still not able to get the 20mm watchman flx pro closure device to have enough compression.The was sheath and the 20mm watchman flx pro closure device were removed from the left atrium and after about 20-30 minutes, the non-bsc closure device was available.The physician attempted with the original transseptal puncture but ended up having to re-stick.The non-bsc 18mm closure device was implanted.After the procedure, during the post-procedure echocardiography, the patient developed agonal breathing and began to decompensate.Chest compressions began.The physician attempted to place a drain bedside but was unable.The patient was transferred to the catheterization laboratory for a pericardiocentesis, but no blood or clot could be removed from the pericardial sac.A cardiac surgeon was brought in and performed a cardiac window.Clot was removed but the patient kept bleeding and passed away on the table.
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 # m635wu60200 batch # 0037353617.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 no 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 pericardial effusion (pe) (additional device required, resuscitation, blood transfusion, surgical intervention) and death.Risk review: a risk review was completed and confirmed that the events of pericardial effusion (pe) and death 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 known inherent risk of device.

• 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: 24519581
• Report Number: 2124215-2026-12257
• Device Sequence Number: 12869359
• Product Code: NGV
• UDI-Device Identifier: 00191506004583
• UDI-Public: (01)00191506004583(17)280901(10)37353617
• Combination Product (Y/N): N
• Initial Reporter State: AZ
• 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: Health Professional,Company Representative
• Initial Reporter Occupation: Other Health Care Professional
• Type of Report: Initial,Followup
• Report Date (Section B): 04/07/2026

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: M635WU60200
• Device Catalogue Number: M635WU60200
• Device Lot Number: 0037353617
• 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: 02/24/2026
• Supplement Date Received by Manufacturer: 04/01/2026
• Initial Report FDA Received Date: 03/05/2026
• Supplement Report FDA Received Date: 04/07/2026
• Date Device Manufactured: 09/02/2025
• 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; Life Threatening; Death
• Patient Age: 85 YR
• Patient Sex: Female