Isoflex™ 1948-58Recalls & reported problems

Summary

The FDA's MAUDE database contains 2,015 adverse event reports that list this exact device (DI 05414734502351), received between Jun 11, 2018 and Sep 28, 2026 — classified as 26 deaths, 931 injuries, 1,058 malfunctions.

The most frequently reported specific device problem is “Over-Sensing” (662 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 2,015 reports, in the reporter's own words as published by the FDA.

• InjurySep 28, 2026Capturing Problem; Device Sensing Problem

  It was reported that the patient presented to the hospital for a scheduled pacemaker replacement procedure and extraction of the right ventricular (RV) leads. The patient had experienced syncope and dizziness associated with diminishing R-wave amplitudes and elevated capture thresholds related to both the active and previously capped RV leads. Fluoroscopic evaluation confirmed that the active RV lead had become dislodged. During the procedure, the pacemaker and active RV lead were explanted and replaced. The previously capped RV lead was also explanted on (b)(6) 2026. Subsequently, a new leadless pacemaker system was implanted. The patient remained stable throughout the procedure.

  Patient problems: Dizziness; Syncope/Fainting

  MAUDE report 50914704 ↗
• InjurySep 28, 2026Capturing Problem; Device Sensing Problem; Device Dislodged or Dislocated

  It was reported that the patient presented to the hospital for a scheduled pacemaker replacement procedure and extraction of the right ventricular (RV) leads. The patient had experienced syncope and dizziness associated with diminishing R-wave amplitudes and elevated capture thresholds related to both the active and previously capped RV leads. Fluoroscopic evaluation confirmed that the active RV lead had become dislodged. During the procedure, the pacemaker and active RV lead were explanted and replaced. The previously capped RV lead was also explanted on (b)(6) 2026. Subsequently, a new leadless pacemaker system was implanted. The patient remained stable throughout the procedure.

  Patient problems: Dizziness; Syncope/Fainting

  MAUDE report 50914700 ↗
• MalfunctionSep 28, 2026Break

  It was reported that the patient presented to hospital for a generator change procedure. During the procedure, it was noted visually that the right ventricular (RV) lead had an insulation breach. The RV lead was capped and replaced on (b)(6) 2026. The patient was in stable condition.

  Patient problems: No Clinical Signs, Symptoms or Conditions

  MAUDE report 50910768 ↗
• MalfunctionSep 24, 2026Fracture; Over-Sensing

  During remote follow-up, noise resulting in oversensing and pacing inhibition were observed on the right ventricular (RV) lead. The patient is pacemaker dependent; however, no consequence occurred due to the inhibition. 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 50884211 ↗
• MalfunctionSep 18, 2026High impedance; Capturing Problem

  Patient problems: No Clinical Signs, Symptoms or Conditions

  MAUDE report 50829144 ↗
• MalfunctionSep 17, 2026High impedance

  It was reported that the patient presented remotely via Merlin.net. Review of transmission, it was noted that the right ventricular (RV) lead exhibited gradual increase of pacing impedance. No changes or interventions were reported and will continue to be monitored. There were no patient consequences.

  Patient problems: No Clinical Signs, Symptoms or Conditions

  MAUDE report 50798313 ↗
• InjurySep 14, 2026Adverse Event Without Identified Device or Use Problem

  It was reported that the patient presented to the hospital and experienced symptoms related to right ventricular (RV) lead pacing. The RV lead was explanted and replaced with a left bundle branch area (LBBA) lead. Multiple repositioning attempts were made on the LBBA lead. The LBBA lead was unsuccessfully implanted during the same procedure and was replaced on (b)(6) 2026. There were no patient consequences.

  Patient problems: Insufficient Information

  MAUDE report 50749636 ↗
• InjurySep 14, 2026Adverse Event Without Identified Device or Use Problem

  It was reported that the patient presented for a scheduled clinic visit due to heart failure. Interrogation revealed that reduced pacing function and low-voltage measurements on the right ventricular (RV) lead associated with cardiomyopathy. An echocardiogram confirmed reduced low voltage function. The RV lead was capped and replaced on (b)(6)2026. The patient condition was not reported.

  Patient problems: Heart Failure/Congestive Heart Failure

  MAUDE report 50748137 ↗
• MalfunctionSep 11, 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 ventricular (RV) lead was failed to pace. The RV lead was not used. The patient was in stable condition.

  Patient problems: No Clinical Signs, Symptoms or Conditions

  MAUDE report 50726845 ↗
• InjurySep 11, 2026Adverse Event Without Identified Device or Use Problem

  It was reported that the patient presented for a post-operative follow-up. It was noted that the patient repeatedly developed pocket infections associated with redness, swelling, and ulceration. The wound remained open, with the pacemaker exposed, despite two debridement procedures. A small portion of heart tissue was observed on the lead. The physician believed that the infection was device and procedure related. The entire system, including the pacemaker, and the right ventricular lead, was explanted and replaced with a leadless pacemaker. The patient remained in stable condition.

  Patient problems: Unspecified Infection

  MAUDE report 50725407 ↗
• MalfunctionSep 9, 2026High impedance; Device Dislodged or Dislocated

  Patient problems: No Clinical Signs, Symptoms or Conditions

  MAUDE report 50681226 ↗
• MalfunctionAug 26, 2026Failure to Capture; Device Dislodged or Dislocated

  It was reported that the patient presented to the hospital for a scheduled implant procedure. During the procedure, the right ventricular (RV) lead exhibited a high capture threshold, resulting in loss of capture. Diagnostic imaging confirmed that the RV lead had become dislodged. The physician attempted to reposition the lead but was unsuccessful. The RV lead was subsequently removed and replaced. The patient remained in stable condition.

  Patient problems: No Clinical Signs, Symptoms or Conditions

  MAUDE report 50445242 ↗
• MalfunctionAug 19, 2026High impedance

  It was reported that the patient presented for an implant procedure. During the procedure, it was noted that the right ventricular (RV) lead exhibited high pacing impedance. The RV lead was not used. The patient remained in stable condition.

  Patient problems: No Clinical Signs, Symptoms or Conditions

  MAUDE report 50314094 ↗
• MalfunctionAug 14, 2026Break

  Patient problems: No Clinical Signs, Symptoms or Conditions

  MAUDE report 50257528 ↗
• MalfunctionAug 13, 2026Signal Artifact/Noise

  It was reported that the patient presented for a follow up in clinic. It was noted that the right ventricular lead exhibited noise. No intervention was performed. There were no patient consequences.

  Patient problems: No Clinical Signs, Symptoms or Conditions

  MAUDE report 50231796 ↗
• InjuryAug 11, 2026Break

  It was reported that the patient presented with syncope. It was noted that the right ventricular (RV) lead and right atrial (RA) lead were found to be broken. Both the RV and RA leads were explanted, and a dual-chamber leadless pacemaker was implanted on (b)(6)2026. Patient status was not reported.

  Patient problems: Syncope/Fainting

  MAUDE report 50205216 ↗
• MalfunctionAug 7, 2026No Apparent Adverse Event

  This report is to advise of an event observed during analysis.

  Patient problems: Insufficient Information

  MAUDE report 50181918 ↗
• InjuryAug 7, 2026Over-Sensing

  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 50176055 ↗
• MalfunctionAug 7, 2026Signal Artifact/Noise

  Patient problems: No Clinical Signs, Symptoms or Conditions

  MAUDE report 50170356 ↗
• 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 25728454 ↗
• InjuryJul 5, 2026Failure to Disconnect; Device Dislodged or Dislocated

  IT WAS REPORTED THAT THE PATIENT'S PACEMAKER HAD MIGRATED AND THE RIGHT ATRIAL (RA), RIGHT VENTRICULAR (RV) AND LEFT VENTRICULAR (LV) LEADS WERE ALL DISLODGED AND TWISTED AROUND ONE ANOTHER. FLUOROSCOPY CONFIRMED BOTH THE PACEMAKER MIGRATION AND THE DISLODGEMENT OF ALL THREE LEADS. THE PACEMAKER WAS REPOSITIONED ON (B)(6) 2026 AND THE THREE LEADS WERE EXPLANTED AND REPLACED. THE PATIENT REMAINED STABLE THROUGHOUT THE PROCEDURE.

  Patient problems: No Clinical Signs, Symptoms or Conditions

  MAUDE report 25713134 ↗
• InjuryJul 3, 2026Failure to Capture; Device Dislodged or Dislocated

  IT WAS REPORTED THAT THE PATIENT PRESENTED FOR AN EXPLANT PROCEDURE. PRIOR TO THE PROCEDURE, IT WAS NOTED THAT THE RIGHT VENTRICULAR (RV) LEAD HAD MICRO-DISLODGED AND EXHIBITED FAILURE TO CAPTURE. THE DISLODGEMENT OF THE LEAD WAS VERIFIED BY FLUOROSCOPY. THE RV LEAD WAS EXPLANTED AND REPLACED. THE PATIENT WAS IN STABLE CONDITION THROUGHOUT THE PROCEDURE.

  Patient problems: No Clinical Signs, Symptoms or Conditions

  MAUDE report 25700744 ↗
• InjuryJun 30, 2026Over-Sensing

  ADDITIONAL INFORMATION WAS RECEIVED THAT PROVOCATIVE TESTING WAS PERFORMED AND THE NOISE WAS REPRODUCIBLE. THE LEAD WAS CAPPED AND REPLACED TO RESOLVE THE EVENT.

  Patient problems: No Clinical Signs, Symptoms or Conditions

  MAUDE report 25669420 ↗
• InjuryJun 29, 2026Over-Sensing

  IT WAS REPORTED THAT THE PATIENT PRESENTED TO CLINIC FOR A FOLLOW UP. IT WAS NOTED THAT THE RIGHT VENTRICULAR (RV) LEAD EXHIBITED OVERSENSING NOISE RESULTING IN PACING INHIBITION. THE RV LEAD WAS CAPPED AND REPLACED ON (B)(6) 2026. THE PATIENT WAS IN STABLE CONDITION.

  Patient problems: No Clinical Signs, Symptoms or Conditions

  MAUDE report 25648954 ↗
• MalfunctionJun 25, 2026Break; Over-Sensing

  DURING AN IN-CLINIC FOLLOW-UP, NOISE THAT RESULTED IN OVER-SENSING WAS OBSERVED ON THE RIGHT VENTRICULAR (RV) LEAD. THE SUSPECTED CAUSE OF THE EVENT WAS DUE TO INSULATION DAMAGE, ALTHOUGH NOT CONFIRMED. NO INTERVENTION HAS BEEN PERFORMED. THE PATIENT WAS STABLE AND WILL CONTINUE TO BE MONITORED.

  Patient problems: No Clinical Signs, Symptoms or Conditions

  MAUDE report 25628118 ↗