Merlin™ 3650Recalls & reported problems
St. Jude Medical, Inc. · Patient Care System (Merlin™ PCS) · Class 3
Data updated Oct 13, 2026 from official FDA records · Editorial policy
Quick summary
This St. Jude Merlin patient care system is a programmer used to check and adjust implanted heart devices. Its 382 reports include 1 death and 35 injuries, and mostly describe incorrect measurements during checks, with some reports of programmers freezing or smoking. Some injury reports describe pauses or slowing of the heartbeat during testing. The 1 recall, now closed, started in February 2020 and concerned a software fault in shock energy settings.
AI-generated from the FDA records on this page and checked automatically against the numbers below. Read the details before relying on it.
- Adverse event reports
- 380
- Deaths reported
- 1
- Injuries reported
- 35
- Recalls naming it
- 1
Summary
The FDA's MAUDE database contains 380 adverse event reports that list this exact device (DI 05414734500661), received between Jul 10, 2018 and Aug 18, 2026 — classified as 1 death, 35 injuries, 344 malfunctions.
The most frequently reported specific device problem is “Incorrect Measurement” (230 reports).
1 FDA recall record name this device's identifier.
Reports come from manufacturers, hospitals and patients and are not verified by the FDA. A report does not prove the device caused the event, and counts can't be used to compare devices or estimate failure rates. How this data works · Data updated Oct 13, 2026.
Reports received per month
Recalls naming this device
- Feb 28, 2020Terminated
Internal testing of software identified software anomaly scenarios where if non-applicable shock energy value is selected, the device will continue to use the previously programmed energy level and the user will not be alerted that the selected value was not retained.
Z-1700-2020 · Root cause: Under Investigation by firm · FDA record ↗
Most reported problems
Device problems
- Incorrect Measurement230
- Failure to Interrogate25
- Program or Algorithm Execution Failure24
- Smoking16
- Application Program Freezes or Fails to Launch15
- Sparking14
- Unintended Electrical Shock14
- Thermal Decomposition of Device12
Patient problems
- No Clinical Signs, Symptoms or Conditions283
- No Known Impact Or Consequence To Patient34
- Arrhythmia23
- Discomfort11
- No Patient Involvement11
- Dizziness7
- Insufficient Information6
- Syncope/Fainting5
Recent adverse event reports
The 25 most recent of 380 reports, in the reporter's own words as published by the FDA.
InjuryAug 18, 2026Adverse Event Without Identified Device or Use Problem
It was reported that the patient experienced loss of capture in the ventricle during an atrial capture threshold test. As a result, the patient experienced asystole. No intervention was reported to resolve the event. Abbott Technical Support reviewed the device session records and stated the event was due to a normal device behavior during the atrial capture threshold test. The RV pulse amplitude automatically becomes the last programmed fixed pulse amplitude which fell below the capture threshold required to stimulate the patient. The patient was in stable condition.
Patient problems: Arrhythmia
MAUDE report 50308016 ↗InjuryJul 31, 2026Application Program Freezes or Fails to Launch
It was reported that a programmer became frozen during the sense test for a right atrial (RA) leadless pacemaker (LP). The LP had been programmed to a lower pacing rate for the test and there was no way to end it or reprogram. The test was also unsuccessful as the LP failed to sense, which was the same result from implant. The programmer power supply was accidentally unplugged, but the RA LP was still set to the lower pacing rate and unable to sense. The programmer test was then successfully ended on its own. Patient was stable with no other symptoms.
Patient problems: Arrhythmia
MAUDE report 50107404 ↗MalfunctionJun 11, 2026Device Emits Odor; Smoking
THE HEALTHCARE PROVIDER ATTEMPTED TO TURN ON THE PROGRAMMER AND IT BEGAN TO SMOKE AND A BURNT SMELL WAS OMITTED. NO PATIENT WAS INVOLVED AND NO CONSEQUENCE TO THE HEALTH CARE PROVIDER.
Patient problems: No Clinical Signs, Symptoms or Conditions
MAUDE report 25466189 ↗MalfunctionMay 12, 2026Unintended Electrical Shock
IT WAS REPORTED THAT THE USER WAS SHOCKED BY THE PROGRAMMER. THERE WERE NO ADVERSE CONSEQUENCES AND THE USER WAS STABLE.
Patient problems: Discomfort
MAUDE report 25153417 ↗InjuryApr 20, 2026Interrogation Problem; Application Program Freezes or Fails to Launch
IT WAS REPORTED THAT THE PATIENT PRESENTED POST IMPLANT PROCEDURE FOR FOLLOW-UP. UPON DEVICE INTERROGATION, THERE WAS I2P INTERRUPTION WHILE PERFORMING AN ATRIAL SENSE TEST. THE PROGRAMMER THEN FROZE AND HAD TO BE RESTARTED AS A RESULT. DURING THIS TIME THE PATIENT EXPERIENCED BRADYCARDIA FOR LONGER THAN EXPECTED. AFTER TURNING THE PROGRAMMER OFF AND THEN BACK ON THE PACING BASE RATES WERE SUCCESSFULLY RE-ESTABLISHED. THE PATIENT WAS IN STABLE CONDITION.
Patient problems: Arrhythmia
MAUDE report 24927920 ↗MalfunctionApr 13, 2026Incorrect Measurement
IT WAS REPORTED THAT THE PROGRAMMER EXHIBITED AN INCORRECT LONGEVITY ESTIMATE BECAUSE OF A BATTERY LONGEVITY CALCULATION OVERESTIMATION. NO PATIENT COMPLICATIONS HAVE BEEN REPORTED AS A RESULT OF THIS EVENT.
Patient problems: No Clinical Signs, Symptoms or Conditions
MAUDE report 24867616 ↗MalfunctionApr 11, 2026Smoking; Excessive Heating
IT WAS REPORTED THAT THE PROGRAMMER WAS EMITTING SMOKE. THERE WERE NO ADVERSE CONSEQUENCES.
Patient problems: No Clinical Signs, Symptoms or Conditions
MAUDE report 24847359 ↗MalfunctionApr 8, 2026Failure to Interrogate
IT WAS REPORTED THAT THE PATIENT PRESENTED IN CLINIC FOR FOLLOW-UP. DURING THE VENTRICULAR CAPTURE TESTING, IT WAS FOUND THAT THE RIGHT VENTRICULAR LEADLESS PACEMAKER LOST ITS CONDUCTIVE TELEMETRY WITH THE PROGRAMMER AND RESULTED IN FAILURE TO CAPTURE. NO INTERVENTION WAS PERFORMED. PATIENT CONDITION WAS STABLE.
Patient problems: No Clinical Signs, Symptoms or Conditions
MAUDE report 24821453 ↗MalfunctionApr 8, 2026Interrogation Problem
IT WAS REPORTED THAT THE PATIENT PRESENTED TO THE HOSPITAL FOR A LEADLESS PACEMAKER (LP) IMPLANT PROCEDURE. WHILE CONDUCTING A PACING CAPTURE THRESHOLD (PCT) TEST, TELEMETRY WAS LOST BETWEEN THE LP AND PROGRAMMER. THE CAPTURE TEST COULD NOT BE TERMINATED, AND THE PROGRAMMER WAS TURNED OFF. AFTERWARDS, IT WAS DIFFICULT TO RE-ESTABLISH TELEMETRY AND THE IMPLANT COULD NOT BE FINALIZED. IT WAS SUSPECTED THAT THE LOSS OF TELEMETRY WAS DUE TO NOISE INTERFERENCE FROM A PACING CATHETER WHICH WAS REQUIRED TO STIMULATE THE PATIENT WHO WAS PACEMAKER DEPENDENT. THE PHYSICIAN THEN REDUCED THE RHYTHM AND POWER FROM THE PACING CATHETER, AND THEY WERE ABLE TO RE-ESTABLISH TELEMETRY AND FINALIZE THE IMPLANT FOR THE LP. THERE WAS NO ADVERSE CONSEQUENCE TO THE PATIENT AND THE PATIENT REMAINED IN STABLE CONDITION.
Patient problems: No Clinical Signs, Symptoms or Conditions
MAUDE report 24821195 ↗InjuryMar 12, 2026Display or Visual Feedback Problem; Application Program Freezes or Fails to Launch; Program or Algorithm Execution Failure
DURING AN IN-CLINIC CAPTURE THRESHOLD TESTING, THE USER RELEASED THE BUTTON TO TERMINATE THE TESTING AS EXPECTED, HOWEVER, THE PROGRAMMER SCREEN FLICKERED AND THE SOFTWARE FROZE WITH THE SUSTAINED DECREMENT, RESULTING IN LOSS OF CAPTURE, AND PATIENT SYNCOPE. SHORTLY, BACKUP PACING WAS ENABLED, AND THE PACING FUNCTION WAS RESTORED. PATIENT CONDITION WAS STABLE.
Patient problems: Syncope/Fainting
MAUDE report 24585984 ↗MalfunctionMar 11, 2026Noise, Audible; Unintended Electrical Shock
IT WAS REPORTED THAT UPON SWITCHING THE PROGRAMMER ON, A CRACKLING SOUND WAS HEARD AND THE USER RECEIVED A SMALL ELECTRIC SHOCK FROM THE PROGRAMMER. NO CONSEQUENCES TO THE USER AND NO MEDICAL INTERVENTION WAS REQUIRED. THE PROGRAMMER WAS NO LONGER USED AND WAS REPLACED.
Patient problems: Discomfort
MAUDE report 24573176 ↗MalfunctionJan 6, 2026Poor Quality Image; Device Emits Odor
IT WAS REPORTED THAT, THE TOUCHSCREEN OF THE PROGRAMMER WAS DIM. ADDITIONALLY, BURNT SMELLS WERE BEING EMITTED FROM THE PROGRAMMER. NO ADDITIONAL INTERVENTION WAS PERFORMED. THE PATIENT WAS STABLE.
Patient problems: No Clinical Signs, Symptoms or Conditions
MAUDE report 23974568 ↗MalfunctionNov 20, 2025Device Emits Odor; Smoking; Device Emits Odor; Smoking
DURING AN IN CLINIC FOLLOW UP, THE PROGRAMMER WAS IN USE AND BEGAN SMOKING AND EMITTING AN ODOR. THERE ARE NO PATIENT CONSEQUENCES.
Patient problems: No Clinical Signs, Symptoms or Conditions
MAUDE report 23610643 ↗InjuryJul 1, 2025Application Program Freezes or Fails to Launch; Application Program Freezes or Fails to Launch
DURING FOLLOW-UP, A CAPTURE TEST AS PERFORMED. A DELAY IN PROGRAMMING WAS OBSERVED DURING THE CAPTURE TEST, RESULTING IN SYNCOPE FOR THE PATIENT. THE PATIENT WAS STABLE AND THERE WERE NO FURTHER ADVERSE CONSEQUENCES. ADDITIONAL INFORMATION WAS REQUESTED BUT WAS NOT AVAILABLE.
Patient problems: Syncope/Fainting
MAUDE report 22372183 ↗MalfunctionMay 12, 2025Computer Software Problem; Computer Software Problem
IT WAS REPORTED THAT DEPENDENT PATIENT PRESENTED IN CLINIC FOR ROUTINE AVEIR DR CHECK WHERE THE PATIENT UNDERWENT A VENTRICULAR THRESHOLD DECREMENT TEST. IT WAS NOTED THAT THE LEADLESS PACEMAKER (LP) APPROPRIATELY LOST CAPTURE UPON DECREMENTING, HOWEVER WHEN ENDING THE TEST, THE PROGRAMMER EXHIBITED A SLOW RESPONSE TO THE COMMAND AND THE COMPUTER SOFTWARE TOOK A FEW SECONDS TO RESPOND AND INCREASE THRESHOLD. AS A RESULT, THE PATIENT TO BECAME PRE-SYNCOPAL WITH SYMPTOMS OF DIZZINESS DUE TO THE LAG IN PACING SUPPORT. NO INTERVENTION WAS PERFORMED AS THE DEVICE FUNCTION RETURNED TO NORMAL AFTER THE DELAY. THE PATIENT'S CONDITION WAS STABLE.
Patient problems: Dizziness
MAUDE report 22003907 ↗MalfunctionApr 25, 2025Smoking; Smoking
IT WAS REPORTED THAT THE PROGRAMMER WAS OBSERVED EMITTING SMOKE. THE PROGRAMMER WAS REMOVED FROM SERVICE. THERE WERE NO ADVERSE HEALTH CONSEQUENCES TO CLINICIANS OR PATIENTS.
Patient problems: No Clinical Signs, Symptoms or Conditions
MAUDE report 21910605 ↗MalfunctionJan 29, 2025Interrogation Problem; Interrogation Problem
RELATED MANUFACTURER REFERENCE NUMBER: 2017865-2025-11845. IT WAS REPORTED THE PATIENT PRESENTED FOR IMPLANT PROCEDURE. WHILE FINALIZING THE PROGRAMMING ON THE LEADLESS PACEMAKER (LP), CONDUCTIVE TELEMETRY WITH THE PROGRAMMER FAILED WHICH CAUSED THE LP TO REPROGRAM ITSELF. THE LP WAS SUCCESSFULLY RESTORED. THERE WERE NO PATIENT CONSEQUENCES.
Patient problems: No Clinical Signs, Symptoms or Conditions
MAUDE report 21266824 ↗InjuryJan 16, 2025Computer Software Problem; Communication or Transmission Problem; Interrogation Problem; Computer Software Problem; Communication or Transmission Problem; Interrogation Problem
IT WAS REPORTED THAT THE PROGRAMMER WAS UNABLE TO PROGRAM THE IMPLANTED DEVICE TO A HIGHER PACING RATE. THE PROGRAMMER WAS TURNED OFF AND BACK ON, BUT IT TOOK A LONG TIME TO BOOT UP. AS A RESULT, THE PATIENT EXPERIENCED ARRHYTHMIA AND DISCOMFORT. A TEMPORARY LEAD WAS IMPLANTED TO PACE THE PATIENT AT AN ACCEPTABLE RATE. ADDITIONALLY, IT WAS NOTED THAT THE PROGRAMMER TOOK A LONG TIME TO INTERROGATE THE DEVICE IN ORDER TO REPROGRAM THE DEVICE. THE PROGRAMMER WILL BE RETURNED AND REPLACED TO RESOLVE THE EVENT. THE PATIENT WAS IN STABLE CONDITION.
Patient problems: Arrhythmia; Discomfort
MAUDE report 21169652 ↗MalfunctionDec 12, 2024Break; Thermal Decomposition of Device; Defective Device; Data Problem; Break; Thermal Decomposition of Device; Defective Device; Data Problem
IT WAS REPORTED THAT DURING TECHNICAL INSPECTION, THE MERLIN PROGRAMMER EXHIBITED BURNT MONITOR, ERROR MESSAGE, MOTHERBOARD DEFECT, DAMAGED FAIRINGS, TOP AND BOTTOM DISPLAY COVERS, POWER SUPPLY AND PRINTER. NO RESOLUTION WAS REPORTED. THERE WAS NO PATIENT INVOLVEMENT.
Patient problems: No Clinical Signs, Symptoms or Conditions
MAUDE report 20920343 ↗MalfunctionDec 12, 2024Unintended Electrical Shock; Unintended Electrical Shock
IT WAS REPORTED THAT MERLIN PROGRAMMER EXHIBITED VOLTAGE LEAK AND SHOCKS THE PERSON TRYING TO USE IT. THE PROGRAMMER WAS REPLACED. THERE WAS NO PATIENT INVOLVED.
Patient problems: No Clinical Signs, Symptoms or Conditions
MAUDE report 20914554 ↗MalfunctionNov 19, 2024Device Emits Odor; Device Emits Odor
IT WAS REPORTED THAT MERLIN PROGRAMMER EMITTED BURNING SMELL. THE MERLIN PROGRAMMER WAS NOT USED AND REPLACED WITH NEW DEVICE. THERE WERE NO PATIENT CONSEQUENCES.
Patient problems: No Clinical Signs, Symptoms or Conditions
MAUDE report 20726013 ↗MalfunctionNov 14, 2024Program or Algorithm Execution Problem; Program or Algorithm Execution Problem
IT WAS REPORTED THE DEVICE WAS SUBJECT TO THE DECREMENT TEST FIELD ACTION ISSUED BY ABBOTT ON (B)(6) 2022. NO ARRYTHMIA OR ADVERSE PATIENT CONSEQUENCES WERE REPORTED.
Patient problems: No Clinical Signs, Symptoms or Conditions
MAUDE report 20692044 ↗MalfunctionSep 26, 2024Break; Smoking; Noise, Audible; Tactile Prompts/Feedback; Break; Smoking; Noise, Audible; Tactile Prompts/Feedback
IT WAS REPORTED, SMOKE WAS OBSERVED COMING OUT OF THE MERLIN PROGRAMMER WHILE IN USE. ADDITIONALLY, IT WAS NOTED THE PROGRAMMER WAS AUDIBLY BUZZING, THE TOUCHSCREEN WAS NO LONGER WORKING AS INTENDED AND THE HANDLE AND PRINTER WERE BROKEN. THE USER OF THE MERLIN PROGRAMMER AND THE PATIENT WERE NOT HARMED. THE MERLIN PROGRAMMER IS NO LONGER IN USE.
Patient problems: No Clinical Signs, Symptoms or Conditions
MAUDE report 20309440 ↗MalfunctionSep 5, 2024Thermal Decomposition of Device; Smoking; Sparking; Thermal Decomposition of Device; Smoking; Sparking
IT WAS REPORTED THAT THE MERLIN PROGRAMMER EXHIBITED SPARKS, SMOKE, AND BURNING EFFECTS DURING THE PROGRAMMING SESSION. THE PROGRAMMER WAS NOT USED. THE PATIENT EXPERIENCED NO ADVERSE EFFECTS AND REMAINED IN STABLE CONDITION.
Patient problems: No Clinical Signs, Symptoms or Conditions
MAUDE report 20145861 ↗InjuryAug 22, 2024No Display/Image; Noise, Audible; Unintended Electrical Shock; No Display/Image; Noise, Audible; Unintended Electrical Shock
IT WAS REPORTED THAT THE PROGRAMMER EXHIBITED AN UNINTENDED ELECTRICAL SHOCK UPON A CLINICIAN AND FELT PAIN AS A RESULT. AN AUDIBLE POP SOUND WAS HEARD, AND THE PROGRAMMER'S DISPLAY WENT BLACK. THE PROGRAMMER WAS REPLACED. THERE WERE NO CONSEQUENCES, AND NO PATIENT INVOLVEMENT.
Patient problems: Discomfort
MAUDE report 20028741 ↗
Other Defibrillator, automatic implantable cardioverter, with cardiac resynchronization (CRT-D) devices
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Sources and updates
- Device record: FDA GUDID, file dated Oct 13, 2026 · View this device in AccessGUDID ↗
- Adverse event reports: FDA MAUDE, file dated Oct 13, 2026 · each report above links to its original FDA record
- Recalls: FDA Medical Device Recalls, file dated Oct 13, 2026 · each recall links to the FDA recall notice
- Page last rebuilt: Oct 13, 2026. Data downloaded through openFDA, which notes it is not validated for clinical or regulatory use.
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