The Medtronic Marquis ICD family has recently had a clinical advisory issued relating to sudden device failure.  If you have this device implanted, you need to first check if your device is on the advisory list

To check if your device is one which may require further action you need to contact Medtronic patient services at 1-800-551-5544

If Medtronic advises you that your device is subject to this advisory, then you will need to contact our office to schedule a visit with us so we can determine what is the best action to take for you.

Medtronic has set up a special web site detailing some of the issues with this device.  This site can be accessed by clicking here or on the above link entitled "Medtronic info."

The following letter is being given to patients who visit our practice so that they have information regarding their Marquis defibrillator which is under advisory.

Office Letter to Patients; Date or Dispersal 2/21/2005
                     

RE: Clinical advisory regarding Medtronic Marquis series defibrillators

Options for patients with this device

To Our Dear Patients,

You are being given this letter because you have a Medtronic Marquis series defibrillator implanted in you.  Recently, it has become known that this device can randomly and without warning fail.  To date, 9 patients worldwide out of approximately 87,000 devices implanted have been found to have failed Marquis defibrillators.  No deaths or serious injuries as a result of this device failing have been seen worldwide to date.  When this device fails, it simply stops operating.  No pacing of the heart or defibrillation of a potentially life threatening rhythm disorder will be seen should a device fail.  The mechanism of failure of this defibrillator in the 9 patients seen to date relates to the breakdown of insulation in the battery circuit of the device.  A short circuit occurs, the battery is drained to zero and the device therefore shuts down.  There is no way to predict by checking the device if it will subsequently fail.  Should a device fail in a patient, in the majority of situations the patient will be entirely unaware that this has occurred and will only find this out at the next scheduled defibrillator office check when interrogation of the defibrillator shows it to be non-functional.

Medtronic has studied the mechanism of failure carefully and currently predicts that at most 1.5% of devices will fail over the next five years.  Most patients with Marquis defibrillators will need there battery changed anyway sometime within the next five years due to normal battery depletion.  Therefore for 98.5% of the patients (specifically those who will need there device changed sometime within the next five years) the device will continue to function normally until the time it would have needed to be changed anyway.

The rate of failure of this device is low but not zero.  For many patients however even a low failure rate is too high to tolerate.  These patients include those who require continuous pacing or who have ever had a shock from the defibrillator for an otherwise life threatening heart rhythm disorder.  In these patients, a sudden device failure will result in lack of pacing and lack of shock delivery should a life threatening rhythm disorder occur.  In this group of patients, we are advising that all of these devices be replaced with brand new devices.

In other patients, specifically those who have a device implanted because they are at increased risk for life threatening rhythm disorders but have not yet had a life threatening rhythm disorder or require continuous pacing, replacing the device is not mandatory at this time.  Remember, there is a small risk for complications with an elective device exchange.  For example a post-operative infection at the surgical site could occur which might ultimately place the patient at far greater risk then would have been seen by simply leaving the existing device in place.  Thus, replacing every implanted device in existence is ill advised for many patients.

If a patient does not require continuous pacing and has not yet had a spontaneous life threatening rhythm disorder that without a device could have resulted in death, then there are two possible options available for this patient:

1)      Close device follow-up.  The marquis device can be programmed to beep for 30 seconds when a magnet is placed on top of the device.  If the device beeps when a magnet is placed on it, then this device is working normally and will provide 100% of all therapies it was ever intended to provide.  Since this device could still fail randomly in the future, a repeat check of the device with a magnet should be performed periodically.  Since there is no harm to anyone in checking the device with a magnet, we recommend daily magnet checks should patients chose not to replace their device.  Patients can perform this check themselves and should you elect this option, we will teach you how to do this.  For the majority of patients with Marquis defibrillators, this is a conservative, safe, easy and non-invasive approach.  If you elect to follow the device with a magnet, we will give you the magnet and program the device to beep when the magnet is placed on top of it. 

2)      Elective defibrillator exchange.  If after considering the fact in this letter you want the absolute lowest chance of device failure and are willing to accept the small chance for complications from the exchange surgery, then we will be happy to schedule this procedure for you.  If a patient is either unable or unwilling to closely follow the Marquis device, then an elective exchange should also be performed.

Please remember, should you ever receive a shock from your defibrillator, do not place the magnet on the device.  A magnet placed on a defibrillator during an episode of a life threatening rhythm can prevent the defibrillator from treating the rhythm disorder.  As has been the case since your original implant, if you receive a single shock from your device and feel well after the shock, contact us during business hours so you can come to the office and have the device checked.  If you feel poorly after a shock or receive multiple shocks, call 911 for transportation to the hospital

Medtronic has a web site for the public detailing the clinical advisory on this device. The address of this site is http://medtronicinfo.com/overview.asp

You can also access our web site at www.heartrhythmcenter.com and click on the “device advisories” section for a copy of this letter and links to the above site.

We have written this letter since we know this issue can be confusing to patients and wanted you to have something to refer to after your visit with our office today. 

Sincerely,

Robert Fishel,MD FACC                          Faren Angella, MD FACC

Vladamir Rankovic, MD FACC              Mark Freher, MD FACC