MAUDE Adverse Event Report: BOSTON SCIENTIFIC CORPORATION MAESTRO 4000 CONTROLLER; CATHETER, PERCUTANEOUS, CARDIAC ABLATION, FOR TREATMENT OF ATRIAL FLUTTER

Model Number	86248
Medical Device Problem Code	Temperature Problem (3022)
Health Effect - Clinical Code	No Clinical Signs, Symptoms or Conditions (4582)
Date of Event	08/29/2025
Type of Reportable Event	Malfunction
Additional Manufacturer Narrative
It was indicated that the device will not be returned for evaluation.If there is any further relevant information obtained, a supplemental medwatch will be filed.
Event or Problem Description
It was reported that poor temperature control was observed.During a radio frequency (rf) ablation procedure to treat an atrial fibrillation (a fib) and an atrial flutter, a maestro 4000 generator was selected for use.Account was performing rf cavotricuspid isthmus (cti) line post faraview case with 10mm blazer catheter.Bidirectional block was achieved, however, during rf delivery, impedances were observed to be in the high 60s to low 80s, which appeared slightly low.Maestro settings were 100w, 60c, and 120 seconds.The controller was in temperature control mode.Temperatures varied throughout the procedure.At one point, a temperature of 65c with approximately 20 watts triggered a temperature warning, causing the wattage to drop to zero.Product support suspected that, since target temperatures were being reached at times with relatively low power, the controller was continuously attempting to titrate power and recommended using a lower maximum power setting and manually titrating up if needed.The procedure was completed using the original device.There were no patient complications.Equipment is not expected to be returned.On the one incidence the temperature was high and dropped the power to 0, no warning message was described by the tech running the maestro.It may have been on the screen temporarily, but nothing was observed on the screen when the ablation was terminated.No warnings/notifications were displayed on the opal mapping system v6.0.1.Or maestro 4000 generator.No tracking failures were reported.The temperatures were not routinely hitting the 60 degree limit and experimented power issues.Most of the time we were seeing 45 degrees and 25-30 watts of power.This is not an expected observation of normal temperature control rf delivery.
Additional Manufacturer Narrative
Block h11: blocks e1 (initial reporter title, first name, last name, facility name, address 1, city, state, zip/post code, phone, fax), e2, and e3 have been updated based on the additional information received on october 18, 2025.It was indicated that the device will not be returned for evaluation.If there is any further relevant information obtained, a supplemental medwatch will be filed.
Event or Problem Description
It was reported that poor temperature control was observed.During a radio frequency (rf) ablation procedure to treat an atrial fibrillation (a fib) and an atrial flutter, a maestro 4000 generator was selected for use.Account was performing rf cavotricuspid isthmus (cti) line post faraview case with 10mm blazer catheter.Bidirectional block was achieved, however, during rf delivery, impedances were observed to be in the high 60s to low 80s, which appeared slightly low.Maestro settings were 100w, 60c, and 120 seconds.The controller was in temperature control mode.Temperatures varied throughout the procedure.At one point, a temperature of 65c with approximately 20 watts triggered a temperature warning, causing the wattage to drop to zero.Product support suspected that, since target temperatures were being reached at times with relatively low power, the controller was continuously attempting to titrate power and recommended using a lower maximum power setting and manually titrating up if needed.The procedure was completed using the original device.There were no patient complications.Equipment is not expected to be returned.On the one incidence the temperature was high and dropped the power to 0, no warning message was described by the tech running the maestro.It may have been on the screen temporarily, but nothing was observed on the screen when the ablation was terminated.No warnings/notifications were displayed on the opal mapping system v6.0.1.Or maestro 4000 generator.No tracking failures were reported.The temperatures were not routinely hitting the 60-degree limit and experimented power issues.Most of the time we were seeing 45 degrees and 25-30 watts of power.This is not an expected observation of normal temperature control rf delivery.

• Brand Name: MAESTRO 4000 CONTROLLER
• Common Device Name: CATHETER, PERCUTANEOUS, CARDIAC ABLATION, FOR TREATMENT OF ATRIAL FLUTTER
• Manufacturer (Section D): BOSTON SCIENTIFIC CORPORATION; 300 boston scientific way; marlborough MA 01752
• Manufacturer (Section G): STELLARTECH RESEARCH CORPORATION; 560 cottonwood drive; milpitas CA 95035
• Manufacturer Contact: mary crawford ; 4100 hamline avenue north; dc a330; saint paul, MN 55112 ; 6514400979
• MDR Report Key: 23077000
• Report Number: 2124215-2025-65248
• Device Sequence Number: 4786075
• Product Code: LPB
• UDI-Device Identifier: 08714729861911
• UDI-Public: (01)08714729861911(11)220511
• Combination Product (Y/N): N
• Initial Reporter State: MI
• Initial Reporter Country: US
• PMA/510(K) Number: P020025
• Number of Events Summarized: 1
• Summary Report (Y/N): N
• Serviced by Third Party (Y/N): Unknown
• Reporter Type: Manufacturer
• Report Source: Health Professional
• Initial Reporter Occupation: Physician
• Type of Report: Initial,Followup
• Report Date (Section B): 10/16/2025

1 Device was Involved in the Event

1 Patient was Involved in the Event

• Is this an Adverse Event Report?: No
• Is this a Product Problem Report?: Yes
• Operator of Device: Health Professional
• Device Model Number: 86248
• Device Catalogue Number: 86248
• Device Lot Number: 0511221966
• 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: 08/29/2025
• Supplement Date Received by Manufacturer: 09/18/2025
• Initial Report FDA Received Date: 09/17/2025
• Supplement Report FDA Received Date: 10/16/2025
• Date Device Manufactured: 05/11/2022
• Is the Device Labeled for Single Use? (Y/N): No
• 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
• Patient Sex: Unknown