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	09/01/2026
Type of Reportable Event	Serious Injury
Event or Problem Description
It was reported that thrombosis occurred.A left atrial appendage (laa) closure procedure was being performed under transesophageal echocardiography (tee) guidance.The patient was not on anticoagulation prior to the procedure, and the laa was confirmed to be free of thrombus before venous access was obtained.Following access, 11,000 units of heparin were administered.A watchman trusteer access system (was) was advanced into the left atrium following transseptal puncture, and a pigtail catheter was placed in the laa.An activated clotting time (act) obtained approximately five minutes after the initial heparin administration was 121 seconds and was considered subtherapeutic.An additional 11,000 units of heparin were administered.When the pigtail catheter was removed, thrombus was visualized on the pigtail catheter while it was outside of the patient.A subsequent act was 280 seconds, and after further imaging assessment, the physicians elected to proceed.The pigtail catheter was reintroduced, and laa angiography was performed.A 27mm watchman flx pro delivery system and closure device (wds) was then advanced.While the wds was being unsheathed to the flex-ball configuration, a second thrombus was visualized within the distal laa near the anterior lobe.The thrombus was not mobile.The wds and was were removed, and the procedure was aborted.Both systems were flushed, and no thrombus was identified within either component.Eliquis was initiated following the procedure.Neurological examination was normal, and the patient remained stable without apparent deficits.The patient was subsequently discharged.

• 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: 50695048
• Report Number: 2124215-2026-48202
• Device Sequence Number: 5891813
• Product Code: DQY
• UDI-Device Identifier: 00191506022310
• Combination Product (Y/N): N
• Initial Reporter State: MI
• 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
• Report Date (Section B): 09/09/2026

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: 0039504190
• 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: 09/01/2026
• Initial Report FDA Received Date: 09/09/2026
• 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: Other
• Patient Age: 74 YR
• Patient Sex: Female