MAUDE Adverse Event Report: BOSTON SCIENTIFIC CORPORATION WATCHMAN TruSteer? Access System; Catheter, percutaneous

Model Number	M635TU90050
Medical Device Problem Code	Adverse Event Without Identified Device or Use Problem (2993)
Health Effect - Clinical Code	Thrombosis/Thrombus (4440)
Date of Event	08/20/2026
Type of Reportable Event	Serious Injury
Event or Problem Description
It was reported that thrombosis occurred.A left atrial appendage closure (laac) procedure was being performed.A watchman trusteer access system (was) was used with a versacross connect to enter the superior vena cava (svc).A full dose of heparin was given and access was gained to the la.Transesophageal echocardiography (tee) imaging confirmed the wire position and also showed a clot was forming on the wire.The dilator was removed and the sheath was advanced closed to the wire, so an attempt could be made to aspirate the clot through the sheath.Part of the clot was pulled into the sheath, but it occluded the sheath so aspiration could not continue.A non-bsc device was attempted, but as it was exchanged out the wire was accidentally pulled into the sheath and sheared off the clot.The clot could not be located in any cardiac chambers, so it was assumed the clot embolized to the arterial or cerebral system.The patient remained stable.The procedure was discontinued and the patient was brought to the intensive care unit (icu).The patient was woken up and given a neurological assessment.The patient status was unchanged compared to prior to the procedure.There were no signs of stroke.Activated clotting time (act) was checked every 15 minutes and were noted as 217, 217, 250 and 216 sequentially.A total dose of 29,000 units of heparin was given.The physician suspected the patient was heparin resistant and that could have been the underlying cause of the rapid thrombus formation on the guidewire.

• Brand Name: WATCHMAN TruSteer? Access System
• Common Device Name: Catheter, percutaneous
• 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: 50602426
• Report Number: 2124215-2026-46806
• Device Sequence Number: 16110795
• Product Code: DQY
• UDI-Device Identifier: 00191506022310
• UDI-Public: (01)00191506022310(17)280415(10)39103239
• Combination Product (Y/N): N
• Initial Reporter State: VA
• Initial Reporter Country: US
• PMA/510(K) Number: K240018
• Number of Events Summarized: 1
• Summary Report (Y/N): N
• Reporter Type: Manufacturer
• Report Source: Health Professional,Company Representative
• Initial Reporter Occupation: Physician
• Type of Report: Initial,Followup,Followup
• Report Date (Section B): 10/01/2026

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: M635TU90050
• Device Catalogue Number: M635TU90050
• Device Lot Number: 0039103239
• 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: Not provided
• Supplement Date Received by Manufacturer: 09/02/2026; 09/30/2026
• Initial Report FDA Received Date: 09/04/2026
• Supplement Report FDA Received Date: 09/09/2026; 10/01/2026
• Date Device Manufactured: 04/16/2026
• 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: Hospitalization; Required Intervention
• Patient Age: 81 YR
• Patient Sex: Male
• Patient Weight: 125 LB