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 Codes	Arrhythmia (1721); Bradycardia (1751); Low Blood Pressure/ Hypotension (1914); Tachycardia (2095); Ventricular Fibrillation (2130); Cardiac Tamponade (2226); Cardiac Perforation (2513); Pericardial Effusion (3271)
Date of Event	02/10/2026
Type of Reportable Event	Serious Injury
Event or Problem Description
It was reported that pericardial effusion (pe), cardiac tamponade, and cardiac perforation occurred requiring surgical intervention.The procedure was aborted.A left atrial appendage (laa) closure procedure was being performed using intracardiac echocardiography (ice) guidance.A 20mm watchman flx pro closure device and delivery system (wds) was advanced into a narrow, pinched appendage anatomy.The initial deployment appeared fully expanded but was positioned distally, leaving proximal pectinate tissue uncovered.The physician performed partial recaptured to reposition the device more proximally; however, resistance was encountered and the wds appeared caught on tissue.Multiple recapture and redeployment attempts were performed.A pe was then noted developing around the transverse sinus region and progressively enlarged rapidly accompanied by hypotension.A transesophageal echocardiogram (tee) was performed and a pericardiocentesis was initiated, and blood was manually aspirated and returned via the groin access site.Despite these efforts, the pe continued to enlarge, and the patient became hemodynamically unstable, requiring cardiopulmonary resuscitation (cpr) which was performed for 30 minutes while efforts for an emergent sternotomy was initiated.The surgeon identified an approximately 2 cm perforation of the laa.A 3 mm clip was applied across the laa (ligation) and the perforation was repaired.Approximately 2 liters of blood were transfused.The laa closure procedure was aborted, without a closure device being implanted.The patient was admitted to the hospital for ongoing management.
Event or Problem Description
It was reported that pericardial effusion (pe), cardiac tamponade, and cardiac perforation occurred requiring surgical intervention.The procedure was aborted.A left atrial appendage (laa) closure procedure was being performed using intracardiac echocardiography (ice) guidance.A 20mm watchman flx pro closure device and delivery system (wds) was advanced into a narrow, pinched appendage anatomy.The initial deployment appeared fully expanded but was positioned distally, leaving proximal pectinate tissue uncovered.The physician performed partial recaptured to reposition the device more proximally; however, resistance was encountered and the wds appeared caught on tissue.Multiple recapture and redeployment attempts were performed.A pe was then noted developing around the transverse sinus region and progressively enlarged rapidly accompanied by hypotension.A transesophageal echocardiogram (tee) was performed and a pericardiocentesis was initiated, and blood was manually aspirated and returned via the groin access site.Despite these efforts, the pe continued to enlarge, and the patient became hemodynamically unstable, requiring cardiopulmonary resuscitation (cpr) which was performed for 30 minutes while efforts for an emergent sternotomy was initiated.The surgeon identified an approximately 2 cm perforation of the laa.A 3 mm clip was applied across the laa (ligation) and the perforation was repaired.Approximately 2 liters of blood were transfused.The laa closure procedure was aborted, without a closure device being implanted.The patient was admitted to the hospital for ongoing management.It was further reported the hemodynamic instability also included bradycardia, tachycardia ,and ventricular tachycardia and ventricular fibrillation.The patient remains hospitalized.
Additional Manufacturer Narrative
B5: information added.H6 patient codes added: bradycardia, tachycardia, ventricular fibrillation, tachycardia.
Additional Manufacturer Narrative
B5: information added.H6: impact code added: unexpected medical intervention.
Event or Problem Description
It was reported that pericardial effusion (pe), cardiac tamponade, and cardiac perforation occurred requiring surgical intervention.The procedure was aborted.A left atrial appendage (laa) closure procedure was being performed using intracardiac echocardiography (ice) guidance.A 20mm watchman flx pro closure device and delivery system (wds) was advanced into a narrow, pinched appendage anatomy.The initial deployment appeared fully expanded but was positioned distally, leaving proximal pectinate tissue uncovered.The physician performed partial recaptured to reposition the device more proximally; however, resistance was encountered and the wds appeared caught on tissue.Multiple recapture and redeployment attempts were performed.A pe was then noted developing around the transverse sinus region and progressively enlarged rapidly accompanied by hypotension.A transesophageal echocardiogram (tee) was performed and a pericardiocentesis was initiated, and blood was manually aspirated and returned via the groin access site.Despite these efforts, the pe continued to enlarge, and the patient became hemodynamically unstable, requiring cardiopulmonary resuscitation (cpr) which was performed for 30 minutes while efforts for an emergent sternotomy was initiated.The surgeon identified an approximately 2 cm perforation of the laa.A 3 mm clip was applied across the laa (ligation) and the perforation was repaired.Approximately 2 liters of blood were transfused.The laa closure procedure was aborted, without a closure device being implanted.The patient was admitted to the hospital for ongoing management.It was further reported the hemodynamic instability also included bradycardia, tachycardia ,and ventricular tachycardia and ventricular fibrillation.The patient remains hospitalized.It was further reported the patient required a tracheostomy tube to be placed.
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 # 0036809708.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 arrhythmia (bradycardia, tachycardia, ventricular tachycardia, ventricular fibrillation), (resuscitation) pericardial effusion with cardiac tamponade (additional device required), perforation, and hypotension (hospitalization, imaging required, blood transfusion, surgical intervention, unexpected medical intervention).Risk review; a risk review was completed and confirmed that the events of arrhythmia (bradycardia, tachycardia, ventricular tachycardia, ventricular fibrillation), pericardial effusion with cardiac tamponade, perforation, and hypotension 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.
Event or Problem Description
It was reported that pericardial effusion (pe), cardiac tamponade, and cardiac perforation occurred requiring surgical intervention.The procedure was aborted.A left atrial appendage (laa) closure procedure was being performed using intracardiac echocardiography (ice) guidance.A 20mm watchman flx pro closure device and delivery system (wds) was advanced into a narrow, pinched appendage anatomy.The initial deployment appeared fully expanded but was positioned distally, leaving proximal pectinate tissue uncovered.The physician performed partial recaptured to reposition the device more proximally; however, resistance was encountered and the wds appeared caught on tissue.Multiple recapture and redeployment attempts were performed.A pe was then noted developing around the transverse sinus region and progressively enlarged rapidly accompanied by hypotension.A transesophageal echocardiogram (tee) was performed and a pericardiocentesis was initiated, and blood was manually aspirated and returned via the groin access site.Despite these efforts, the pe continued to enlarge, and the patient became hemodynamically unstable, requiring cardiopulmonary resuscitation (cpr) which was performed for 30 minutes while efforts for an emergent sternotomy was initiated.The surgeon identified an approximately 2 cm perforation of the laa.A 3 mm clip was applied across the laa (ligation) and the perforation was repaired.Approximately 2 liters of blood were transfused.The laa closure procedure was aborted, without a closure device being implanted.The patient was admitted to the hospital for ongoing management.It was further reported the hemodynamic instability also included bradycardia, tachycardia ,and ventricular tachycardia and ventricular fibrillation.The patient remains hospitalized.It was further reported the patient required a tracheostomy tube to be placed.

• 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: 24345653
• Report Number: 2124215-2026-08542
• Device Sequence Number: 15838094
• Product Code: NGV
• UDI-Device Identifier: 00191506004583
• UDI-Public: (01)00191506004583(17)280621(10)36809708
• Combination Product (Y/N): N
• Initial Reporter State: VA
• 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: Physician
• Type of Report: Initial,Followup,Followup,Followup
• Report Date (Section B): 04/23/2026

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: 0036809708
• 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: 02/10/2026
• Supplement Date Received by Manufacturer: 02/16/2026; 03/10/2026; 04/13/2026
• Initial Report FDA Received Date: 02/16/2026
• Supplement Report FDA Received Date: 03/09/2026; 03/25/2026; 04/23/2026
• Date Device Manufactured: 06/22/2025
• 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; Required Intervention; Life Threatening
• Patient Age: 72 YR
• Patient Sex: Male