In late May, Guidant Corp. (Indianapolis) acknowledged that it had failed to properly inform physicians and patients about a potentially fatal flaw in one of its implantable cardiac defibrillator (ICD) models that resulted in the death of a 21-year-old college student. Since then, new disclosures have continued to deepen the company's problems. Recalls of the company's ICD devices have been expanded to include 11 different models totaling approximately 109,000 units. And the continued drumbeat of negative publicity is threatening to inflict potentially serious market damage on the company's entire line of cardiac rhythm management products.

Of the 11 ICD models recalled by the company, three are believed to have the potential to malfunction due to short-circuiting (Prizm 2, Contak Renewal, and Contak Renewal 2). FDA has classified these as Class I recalls—the most serious level—indicating “a reasonable probability that if a particular device is malfunctioning, it will cause serious adverse health consequences or death.” There is no way to check whether one of these ICDs is prone to short-circuiting or impending device failure. Two deaths have been linked to this particular malfunction. It is believed that 42,000 of these units were manufactured, with about 21,000 still implanted.

As required under the terms of the Class I recall, Guidant has informed physicians and patients about the potential for ICD device malfunction and has issued an advisory and a series of recommendations for proper follow-up actions and procedures. According to FDA, the recall does not necessarily require removal of the device, a decision that should only be made during doctor-patient consultation.

Three of the 11 affected models—representing 21,000 units—can potentially malfunction due to a computer memory error (Ventak Prizm AVT, Vitality AVT, and Renewal AVT). Guidant notes that the computer memory error can be readily detected and the device can be reprogrammed noninvasively during the patient's next visit to the doctor. FDA has classified these as Class II recalls, in which “the malfunctioning product may cause temporary or medically reversible adverse health consequences, although the probability of serious adverse health consequences is remote.” Two adverse incidents, but no deaths, have been associated with the programming error in the ICDs.

According to FDA, the remaining five models in the recall (Contak Renewal 3, Contak Renewal 4, Renewal 3, Renewal 4 AVT, and Renewal RF) are subject to a “component failure that in rare cases may limit available therapy. A magnetic switch in these devices may become stuck in the closed position, which in some cases inhibits the device's ability to treat ventricular or atrial tachyarrhythmias (abnormally fast heart rhythms) and also accelerates battery depletion.” Four such occurrences have been confirmed with one additional incident suspected out of approximately 46,000 devices. FDA has also classified these recalls as Class II.

Schultz: A need for personalized advice.

Commenting on the recalls, Daniel Schultz, MD, director of FDA's Center for Devices and Radiological Health (CDRH), said, “Malfunctions in these devices can lead to serious consequences and it's important for patients to call their doctor for additional information and personalized advice. However, it's also important to understand that in most cases these defibrillators work well and save lives.” Schultz also acknowledged Guidant's worldwide efforts to communicate the details of the recalls to doctors and patients.