Medtronic CRM Product Performance Report

Advisories

7227Cx GEM
7229Cx GEM II VR
Original Date of Advisory: October 15, 1999

Potential Circuit Overload

Product

Model 7227Cx and Model 7229Cx implantable cardioverter defibrillators supplied before October 15, 1999, with serial numbers ending in an “H.” For example, PIPxxxxxxH or PJJxxxxxxH, where x is a variable numeric, may be affected. Specific model and serial numbers of affected devices are available by calling US Technical Services at 1 (800) 723-4636.

IMPORTANT REMINDER:

Medtronic strongly advises physicians who have patients under their care affected by this issue to reprogram the Patient Alert feature “ON” without delay.

Advisory

Manufacturing error in a small percentage of devices may cause circuit overload when AX ≥ B High Voltage energy is delivered via an integrated bipolar lead. GEM Model 7227Cx and GEM II VR Model 7229Cx devices with dedicated bipolar sensing leads are not affected by this issue. Devices affected may not be able to subsequently charge to full energy and experience “charge circuit timeout.”

Patient Management Recommendations

  • Assessment of all patients with the potentially affected devices implanted AND an integrated bipolar ICD lead such as the Models 6942 and 6945 should take place without delay
     
  • Reprogram polarity pathway to B ≥ AX for all cardioversion and defibrillation therapies
     
  • Confirm correct device function:
    • – Perform a full energy charging sequence
    • – If “charge circuit timeout” is observed, contact your Medtronic representative
    • – If device charges normally, it has not been damaged and will function appropriately with polarity programmed B ≥ AX

Recent studies have demonstrated that DFTs are similar or lower in a B ≥ AX polarity pathway when compared to AX ≥ B.

Devices implanted with functional dedicated bipolar leads such as the Models 6932, 6934S, 6936, 6943, and 6966 are not affected.

Status

Device performance related to this advisory continues to be within Medtronic’s engineering projections. Patient management recommendations remain unchanged. Out of the initial implant population of 10,000 in the United States, approximately 1,200 remain implanted. The devices affected by this advisory are nearing the end of their expected battery longevity.