Disturbing uptick in defibrillator recalls

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Disturbing uptick in defibrillator recalls

Most pacemakers and implantable cardioverter/defibrillators work as they should, though the number recalled each year is growing.

Two parallel trends capture the promise and perils of pacemakers and implantable cardioverter/defibrillators (ICDs):

• The number of devices implanted, and the number of lives saved, grows steadily each year.

• So does the number of devices that malfunction or are recalled.

The vast majority of pacemakers and ICDs do their jobs without a hitch. In the 2.6 million devices implanted between 1990 and 2002, just 17,323 (0.66%) malfunctions were confirmed, according to an exhaustive analysis of FDA data by Dr. William H. Maisel of Harvard-affiliated Beth Israel Deaconess Medical Center (see chart). These malfunctions accounted for 61 deaths, or two deaths for every 100,000 devices implanted.

Pacemaker/ICD trends Since 1990, there have been increases in the number of pacemakers and ICDs implanted as well as the number of confirmed malfunctions. Source: Dr. William H. Maisel/FDA

Problems with pacemakers have been declining over the years, while ICD problems are on the rise. That's a troubling trend, since the number of people deemed appropriate to get an ICD has exploded since 2004 as studies have defined larger groups of people who might benefit from them. The increase in malfunctions, along with a rise in recalls, could reflect growing pains for ICD makers, who are trying to make these devices smaller, lighter, more powerful, and more versatile. It could also be a warning that this booming industry needs more oversight.

Pacemakers are used to treat a variety of heart rhythm problems, many of them related to an abnormally slow heartbeat (bradycardia). Some send "squeeze now" signals only when the heart rate falls below a certain number of beats per minute. Others are always on, keeping the heart beating at a steady pace.

Early ICDs were implanted in people who had collapsed suddenly due to a potentially lethal arrhythmia. These "shock boxes" sat patiently and did little more than monitor the heart's rhythm. At the first sign the heart was lapsing into serious trouble, like ventricular tachycardia or ventricular fibrillation, the device delivered a shock that rebooted the heart and restored a healthy rhythm. Today's ICDs can help pace the heart as well as shock it out of a dangerous rhythm. They are being used more and more as a just-in-case safety net for heart attack survivors who have damaged left ventricles but no apparent heart rhythm problem.

Pacemakers and ICDs are implanted just beneath the skin of the upper chest. They range in size from two stacked quarters to a pager. Both run on built-in batteries that power the amazing electronics inside.

Going public

In the summer of 2005, the Guidant Corporation recalled several ICD models — more than 42,000 devices — because of a short circuit that could prevent the device from shocking the heart out of a wayward rhythm. The malfunction caused at least two deaths. The recall came nearly three years after the company first learned about the problem, and just hours before the New York Times ran an article about them. It turned out that the company had fixed the short-circuit problem and notified the FDA of it in 2002, but continued selling devices made before then without telling doctors or people with the potentially faulty ICDs.

In September 2005, the Heart Rhythm Society, an organization of arrhythmia specialists, convened a meeting of cardiologists, FDA officials, and industry representatives to sort out who should be told what, and when, after a company confirms a problem with a pacemaker or ICD.

Dr. Maisel's presentation put the problem of malfunctions in perspective by showing that the number of failures pales in comparison to the number of lives saved. That said, the increase in ICD problems and the disclosure that Guidant knew of malfunctions in some of its ICDs but chose not to act underscore the need for closer monitoring.

At the meeting, the FDA's deputy commissioner for scientific and medical affairs, Dr. Scott Gottlieb, said that the FDA would be more aggressive about getting information on device failures and communicating this information to doctors and the public.

Dealing with recalls

From 1990 to 2005, "advisories" were issued for more than half a million pacemakers and ICDs. These aren't like automobile recalls — you can't drop off your pacemaker or ICD at your cardiologist's office and then run some errands or read a book. The device must be checked, then you and your doctor need to talk about what to do. Replacing a pacemaker or ICD requires an operation, which means a short hospital stay and some recuperation. And like every operation, it can have complications such as bleeding or infection.

Two key factors determine what to do in case of a recall: how dependent you are on your device, and the odds of it failing. If the device is keeping you alive, then even a slim chance of failure may be too high. But if it hasn't gone off in a year or more, and the chances of a malfunction are low, then replacing it could cause more harm than keeping it. For example, following the recall of an Accufix pacemaker in 1994 for breaking wires, more people were harmed by taking out pacemakers with working wires than were harmed by keeping pacemakers with broken ones. Your tolerance for living with a device that might not work when needed is also an important consideration.

The most important thing you can do is to keep in touch with your doctors and make sure they know how to reach you in case there's a problem with your implanted device. The Heart Rhythm Society has developed helpful information sheets on what to do in case of a recall and questions to ask your doctor about one, available at www.hrspatients.org/patients/device_recalls/default.asp.

Last updated:	September 05, 2008