For some patients with serious heart conditions, a defibrillator (a device that helps the heart do its job) can be lifesaving. As with all medical interventions, however, there are benefits and risks. You may have heard about recent studies that report increased rates of infections in patients who've had one of these devices surgically implanted.

There are two main types of implanted defibrillators:  ICDs (implantable cardioverter-defibrillator) and CRT-Ds (cardiac resynchronization Therapy Defibrillator). A defibrillator monitors the electrical activity of the heart. If it detects a potentially dangerous change in the heart's rhythm, it will send small pulses of electricity to shock the heart back into its normal rhythm. Defibrillators are nicknamed "emergency rooms in the chest" because they can intervene when a patient's heart fails, potentially saving the patient's life.

The use of defibrillators doubled between 1993 and 2008. During the same time, the number of implanted device-related infections tripled. While most surgical wounds are likely to become contaminated from bacteria on the skin or in organs, some may progress and become clinical infections. Cardiologists estimate the risk of surgical site infections at five to 20 percent. Infections can prolong patients' hospital stays and may even lead to death. Patients who undergo surgery are also at risk for respiratory, urinary tract, and other bacterial infections.

Defibrillators can fail, especially CRT-Ds. In one study of 3,253 patients who received a CRT-D, 416 had a device-related event by 18 months, and of those, 390 needed surgical intervention. By four years, 50 percent needed surgery to replace the batteries. During the same time, only 10 percent of patients with an ICD needed an intervention (13 percent for dual-chambered ICDs). Furthermore, the rate of infection in patients with a CRT-D was higher. The researchers emphasized, however, that these events were not associated with worse clinical outcomes and did not change the risk of death.

Some heart specialists are also concerned that many patients who receive defibrillators don't actually need them. In one study, researchers found that nine out of 10 patients received no medical benefits from the device.

The FDA collects information about defibrillators, but it's not easy to analyze the data and not all device problems are reported. Furthermore, it's hard to calculate the costs and benefits of cardiac implants and to determine who is actually going to benefit most. If your cardiologist recommends an implanted cardiac device, have a frank discussion with him about all the potential benefits and risks.

 

Sources:

Bakalar, Nicholas. "Risks: Infections Follow Rise in Cardiac Implants." New York Times. Web. 29 August 2011. http://www.nytimes.com/2011/08/30/health/30risks.html?_r=2

HealthGrades. "Defibrillator Implant." Web.
http://www.healthgrades.com/procedures/profile/Defibrillator_Implant

Feder, Barnaby J. "Defibrillators Are Lifesaver, but Risks Give Pause."New York Times. Web. 12 September 2008. http://www.nytimes.com/2008/09/13/business/13defib.html

Douglas, David. "Complex Cardioverter Defibrillators More Problem Prone." Medscape Medical News. Web. 7 June 2011. http://www.medscape.com/viewarticle/744136

Grens, Kerry. "Reports of Defibrillator Failures Incomplete." Medscape Medical News. Web.13 September 2011. http://www.medscape.com/viewarticle/749585

Gifford, C.,BA (Oxon) BMBCh, Christelis, N., MBBCH FRCA FFPMRCA FANZCA, and Cheng, A., MBBS FRACP MPH PhD. "Preventing Postoperative Infection." Continuing Education Anaesthia, Critical Care & Pain 11(5) (2011): 151-156. Medscape Medical News. Web. 27 September 2011. http://www.medscape.com/viewarticle/750224