Isoflex™ 1944-52Recalls & reported problems

Summary

The FDA's MAUDE database contains 1,647 adverse event reports that list this exact device (DI 05414734502320), received between Jun 11, 2018 and Sep 25, 2026 — classified as 12 deaths, 511 injuries, 1,124 malfunctions.

The most frequently reported specific device problem is “Over-Sensing” (418 reports).

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.

Most reported problems

Recent adverse event reports

The 25 most recent of 1,647 reports, in the reporter's own words as published by the FDA.

• InjurySep 25, 2026Adverse Event Without Identified Device or Use Problem

  It was reported that the patient presented for a clinical follow up. It was noted that the patient had experienced persistent redness and swelling at the cervical pocket site, along with symptoms of a pocket infection, for the past six months. The entire system, including the Implantable Cardioverter Defibrillator (ICD), right ventricular lead, right atrial lead, and left ventricular lead, was explanted. The patient remained in stable condition.

  Patient problems: Unspecified Infection

  MAUDE report 50893650 ↗
• MalfunctionSep 24, 2026Fracture; Over-Sensing

  During remote follow-up, noise which resulted in oversensing was observed on the atrial lead. The suspected cause of the event is a lead fracture; however this has not been confirmed. No intervention has been performed at this time. The patient was stable and will continue to be monitored.

  Patient problems: No Clinical Signs, Symptoms or Conditions

  MAUDE report 50884236 ↗
• MalfunctionSep 18, 2026Intermittent Capture; Device Sensing Problem

  It was reported that the patient presented to hospital for an implant procedure. During the procedure, it was noted that the right atrial (RA) lead exhibited inconsistent capture issue and inconsistent P wave measurement. The RA lead was not used and replaced. The patient was in stable condition.

  Patient problems: No Clinical Signs, Symptoms or Conditions

  MAUDE report 50813976 ↗
• MalfunctionSep 14, 2026Component Missing

  It was reported that the patient presented for an implant procedure. During the procedure, it was noted that one of the wing-shaped hooks of the passive right atrial (RA) lead was missing. The RA lead was not used and replaced. The patient remained stable throughout the procedure.

  Patient problems: No Clinical Signs, Symptoms or Conditions

  MAUDE report 50748091 ↗
• InjurySep 8, 2026Over-Sensing; Pacing Problem

  Patient problems: No Clinical Signs, Symptoms or Conditions

  MAUDE report 50680509 ↗
• MalfunctionSep 8, 2026Material Too Rigid or Stiff; Failure to Advance

  It was reported that the patient presented for an implant procedure. During the procedure, the atrial lead was noted to be very stiff, and the stylet could not be advanced to the distal end of the lead. The lead was not used and replaced. The patient was in stable condition.

  Patient problems: No Clinical Signs, Symptoms or Conditions

  MAUDE report 50669293 ↗
• MalfunctionSep 5, 2026Break; Use of Device Problem

  Patient problems: No Clinical Signs, Symptoms or Conditions

  MAUDE report 50632828 ↗
• MalfunctionAug 28, 2026Failure to Capture

  It was reported that the patient presented for an implant procedure. During the procedure, it was noted that the right atrial lead exhibited loss of capture. The lead was not used and replaced during the procedure. The patient remained in a stable condition.

  Patient problems: No Clinical Signs, Symptoms or Conditions

  MAUDE report 50491961 ↗
• MalfunctionAug 28, 2026Break; Over-Sensing

  It was reported that the patient presented for a follow-up in clinic. Interrogation revealed that both the right ventricular (RV) and right atrial (RA) leads exhibited over-sensing attributed to wear and tear. Atrial over-sensing was reproducible with arm movements. No intervention or changes were performed, and the leads will continue to be monitored. The patient was asymptomatic and remained in a stable condition.

  Patient problems: No Clinical Signs, Symptoms or Conditions

  MAUDE report 50491409 ↗
• InjuryAug 27, 2026Device Dislodged or Dislocated

  It was reported that the patient presented to hospital for an implant procedure. Post procedure, it was noted that the right atrial (RA) lead was found dislodged. The RA lead was explanted and replaced. The patient was discharged post procedure.

  Patient problems: No Clinical Signs, Symptoms or Conditions

  MAUDE report 50469161 ↗
• InjuryAug 26, 2026Capturing Problem

  It was reported that the patient's right atrial (RA) lead exhibited high capture threshold. The RA lead was capped and replaced during a scheduled generator exchange procedure on (b)(6) 2026. The patient was stable throughout.

  Patient problems: No Clinical Signs, Symptoms or Conditions

  MAUDE report 50446746 ↗
• MalfunctionAug 26, 2026Detachment of Device or Device Component

  It was reported that the patient presented for an implant procedure. During the procedure, the right atrial (RA) lead suture sleeve did not securely hold the lead body despite multiple attempts at suturing and retracted backward. The physician subsequently selected a screw-in right ventricular (RV) lead; however, the lead exhibited a helix malfunction. As a result, neither the RA lead nor the RV lead was implanted. The physician then selected another screw-in lead, which was successfully implanted in the right atrium. The patient remained in stable condition.

  Patient problems: No Clinical Signs, Symptoms or Conditions

  MAUDE report 50446420 ↗
• MalfunctionAug 25, 2026Over-Sensing

  It was reported that noise leading to oversensing was observed on the right ventricular (RV) lead. Noise was able to be reproduced via provocative testing. No intervention was perfomred; the patient was stable and will continue to be monitored. There were no adverse consequences.

  Patient problems: No Clinical Signs, Symptoms or Conditions

  MAUDE report 50437706 ↗
• MalfunctionAug 21, 2026Failure to Capture

  It was reported that the patient presented for an implant procedure. During the procedure, device interrogation revealed that the atrial lead exhibited loss of capture. The physician subsequently implanted a second atrial lead; however, the second lead also exhibited loss of capture. As a result, both atrial leads were not implanted and were replaced during the same procedure. The patient remained stable throughout the procedure, and no adverse patient consequences were reported.

  Patient problems: No Clinical Signs, Symptoms or Conditions

  MAUDE report 50361510 ↗
• MalfunctionAug 19, 2026Failure to Capture

  It was reported that the patient presented to hospital for an implant procedure. During the procedure, it was noted that the right atrial (RA) lead failed to pace. The RA lead was not used and replaced on (b)(6) 2026. The patient was in stable condition.

  Patient problems: No Clinical Signs, Symptoms or Conditions

  MAUDE report 50312911 ↗
• InjuryAug 12, 2026High impedance; Device Dislodged or Dislocated

  It was reported that the patient presented for an implant procedure. It was noted that the right atrial (RA) lead and right ventricular (RV) lead had dislodged and resulted in high pacing impedance in both leads. The lead dislodgements were confirmed by X-ray. The issue persisted after reopening of the pocket. The pocket was reopened, and the both the leads were explanted. The patient was in a stable condition.

  Patient problems: No Clinical Signs, Symptoms or Conditions

  MAUDE report 50218003 ↗
• InjuryAug 7, 2026Over-Sensing; Pacing Problem

  It was reported that the patient presented for a follow-up visit at the clinic. Upon evaluation, the right atrial (RA) lead and right ventricular (RV) lead exhibited noise reversion episodes that resulted in oversensing. The atrial noise resulted in an inappropriate mode switch. The RA lead and RV lead were capped and replaced with dual-chamber leadless pacing system on (b)(6) 2026. The patient remained in stable condition.

  Patient problems: No Clinical Signs, Symptoms or Conditions

  MAUDE report 50176038 ↗
• MalfunctionAug 6, 2026Difficult to Insert; Product Quality Problem

  Patient problems: No Clinical Signs, Symptoms or Conditions

  MAUDE report 50152300 ↗
• InjuryJul 6, 2026Over-Sensing

  IT WAS REPORTED THAT THE PATIENT PRESENTED REMOTELY VIA MERLIN.NET. UPON REVIEW OF THE TRANSMISSION, IT WAS NOTED THAT THE RIGHT ATRIAL (RA) AND RIGHT VENTRICULAR (RV) LEADS EXHIBITED NOISE OVERSENSING RESULTED IN PACING INHIBITION. THE RA AND RV LEADS WERE EXPLANTED AND REPLACED. THE PATIENT WAS IN STABLE CONDITION THROUGHOUT THE PROCEDURE.

  Patient problems: No Clinical Signs, Symptoms or Conditions

  MAUDE report 25728453 ↗
• MalfunctionJul 2, 2026Use of Device Problem

  IT WAS REPORTED THAT THE PATIENT PRESENTED TO THE HOSPITAL FOR AN IMPLANT PROCEDURE. DURING THE PROCEDURE, THE RIGHT ATRIAL (RA) LEAD COULD NOT BE FIXED TO THE MYOCARDIUM. THE RA LEAD WAS NOT USED AND REPLACED. THE PATIENT WAS IN STABLE CONDITION.

  Patient problems: No Clinical Signs, Symptoms or Conditions

  MAUDE report 25686693 ↗
• MalfunctionJul 1, 2026Device Dislodged or Dislocated

  IT WAS REPORTED THAT THE PATIENT PRESENTED FOR AN IMPLANT PROCEDURE. DURING THE PROCEDURE, THE ATRIAL LEAD WAS FOUND TO BE DISLODGED WHEN IT WAS IMPLANTED, WHICH WAS CONFIRMED BY CHEST X-RAY. AS A RESULT, THE ATRIAL LEAD WAS NOT USED AND REPLACED DURING THE SAME PROCEDURE. THE PATIENT REMAINED STABLE THROUGHOUT THE PROCEDURE.

  Patient problems: No Clinical Signs, Symptoms or Conditions

  MAUDE report 25675072 ↗
• MalfunctionJun 28, 2026High impedance; Capturing Problem; Device Sensing Problem

  IT WAS REPORTED THAT THE PATIENT PRESENTED FOR AN IMPLANT PROCEDURE. DURING PROCEDURE, THE ATRIAL LEAD EXHIBITED HIGH PACING IMPEDANCE, HIGH CAPTURE THRESHOLD AND LOW P- WAVE AMPLITUDE. THE LEAD WAS NOT USED AND REPLACED. THE PATIENT WAS IN STABLE CONDITION.

  Patient problems: No Clinical Signs, Symptoms or Conditions

  MAUDE report 25648498 ↗
• MalfunctionJun 18, 2026Use of Device Problem

  IT WAS REPORTED THAT THE PATIENT PRESENTED FOR AN IMPLANT PROCEDURE. DURING THE PROCEDURE, IT WAS NOTED THAT THE RIGHT ATRIAL (RA) LEAD WAS STUCK AND FAILED TO ADVANCE THROUGH THE SUBCLAVIAN VEIN. DIFFERENT TECHNIQUE WAS USED BUT THE RA LEAD STILL COULD NOT ADVANCE. THE RA LEAD WAS NOT USED AND REPLACED. THE PATIENT WAS LATER DISCHARGED, AND NO PATIENT CONSEQUENCES WERE REPORTED.

  Patient problems: No Clinical Signs, Symptoms or Conditions

  MAUDE report 25555938 ↗
• MalfunctionJun 18, 2026Improper or Incorrect Procedure or Method; Failure to Disconnect

  IT WAS REPORTED THAT DURING THE SURGERY, LOW VOLTAGE LEAD BECAME STUCK IN THE VEIN. THE LEAD WAS NOT USED, AND THE PATIENT'S CONDITION REMAINED STABLE.

  Patient problems: No Clinical Signs, Symptoms or Conditions

  MAUDE report 25552701 ↗
• InjuryJun 17, 2026High impedance; Capturing Problem

  IT WAS REPORTED THAT THE RIGHT ATRIAL LEAD EXHIBITED HIGH CAPTURE THRESHOLDS AND HIGH PACING IMPEDANCE AND THE RIGHT VENTRICULAR LEAD EXHIBITED NOISE. THE RIGHT ATRIAL LEAD WAS CAPPED AND REPLACED ON (B)(6) 2026 AND THE VENTRICULAR LEAD REMAINED IMPLANTED. THE PATIENT WAS IN STABLE CONDITION.

  Patient problems: No Clinical Signs, Symptoms or Conditions

  MAUDE report 25541785 ↗