Simple method to eliminate interference between ventricular assist devices and cardiac rhythm devices

Report on a simple solution to allow programming of defibrillators in the presence of a Heartmate II (Thoratec Corporation, Pleasanton, CA, USA) ventricular assist device. Ventricular assist devices have become increasingly utilized for patients waiting for heart transplantation as well as those who will be maintained on a permanent support. The Heartmate II, which was recently given Food and Drug Administration approval as a bridge-to-transplant device, has a particular anomaly that complicates patient management. The pulse width modulator of the Heartmate II produces electromagnetic noise that interferes with the ability to interrogate and program certain defibrillators, and explantation of the defibrillator has been reported as the only viable solution.

The authors describe the use of cast-iron pans to reduce the electromagnetic interference between St. Jude Medical's first-generation Atlas family of defibrillators (St. Jude Medical, St. Paul, MN, USA) and the Heartmate II pump.

The use of a simple shielding protocol avoids the need to remove a pre-existing defibrillator from a patient receiving support from the Heartmate II ventricular assist device.

The method described herein is important as future generations of medical devices may present different types of device-device interactions. Simple bedside methods to eliminate interference can potentially help patients who would otherwise need one or another device removed.