The Food and Drug Administration has received from the Guidant Corporation several new reports about recent patient deaths associated with short circuits in company heart devices, agency records show.
The three new cases all occurred after June when Guidant recalled the heart devices at issue. The recalls took place after the company came under scrutiny for failing to promptly warn doctors and patients about the risks of short circuits. The new reports bring the number of known deaths associated with the flaw to seven.
The added reports may reflect the fact that doctors and family members, in light of the attention given to the Guidant devices, are increasingly having the units checked for problems after a heart patient’s death. They also suggest that the devices’ possible contributions to earlier deaths may have gone unnoticed because implanted heart units are not routinely examined post-mortem.
The new data may pose further legal problems for Guidant because the electrical failures, while involving different models, are all related to the company’s use of an insulating material in a way that apparently made it prone to deterioration. The Justice Department, as part of an investigation into Guidant’s handling of safety issues, is looking into its use of that material, called polyimide.
In a statement, Guidant, which is based in Indianapolis, said that it “regularly communicates information about product performance to various stakeholders including physicians and regulatory bodies.” The company also pointed out that it had recently begun publicly releasing more detailed data about product malfunctions.
In 2002, Guidant discovered that one of its heart devices was prone to short-circuiting. Company officials declined to respond yesterday to written questions about the steps Guidant took, if any, at that time to determine if other company heart devices had the same flaw.
Both the F.D.A. and Guidant have told patients with the affected units that they should consult with their doctors to decide whether the risks posed by the device outweighed those posed by replacement surgery. One heart device specialist, Dr. William H. Maisel, who is based in Boston, said yesterday that the new death reports should not necessarily affect those decisions, because most doctors look at a device’s overall failure rate, rather than the percentage of those failures that involve deaths.
Guidant, which is the country’s second-biggest producer of defibrillators and pacemakers, is currently the subject of a bidding war between two corporate suitors, Boston Scientific and Johnson & Johnson. Boston Scientific’s bid of $72 a share for Guidant is substantially higher than a revised deal struck last month between Johnson & Johnson and Guidant, which valued the device maker at $63.08 a share.
The Guidant devices at issue include a defibrillator known as the Prizm 2 DR as well as a combination pacemaker and defibrillator known as the Contak Renewal and a related product, the Contak Renewal 2. A defibrillator senses and interrupts a potentially fatal heart rhythm; a pacemaker regulates a heart that is beating too fast or too slowly.
Heart devices, like defibrillators, are vital products and all manufacturers of them have experienced recalls and problems.
Guidant’s problems came to light in May when The New York Times reported that the company had not told doctors for three years that the Prizm 2 DR had short-circuited and failed more than two dozen times. But internal testing by Guidant as well as reports filed with the F.D.A. by the company indicate that the Contak Renewal and Contak Renewal 2 pose a significantly higher risk. The devices are used in patients with advanced congestive heart failure.
In response to a reporter’s request, the F.D.A. yesterday released recent filings by Guidant in connection with device failures. In a statement, Guidant said there were now five patient deaths associated with short circuits in either a Contak Renewal or a Contak Renewal 2, and two such deaths associated with the Prizm 2 DR.
Apart from the death reports, there are no new filings involving malfunctions of the Contak Renewal devices.
It is difficult to determine the role, if any, that a device played in a patient’s death. But in F.D.A. filings, Guidant reported that it found signs of short-circuiting in the units as well as evidence in the device’s computer memory showing that, in some cases, a unit had failed to provide therapy.
In April 2002, Guidant discovered and fixed the insulation-related problem in the Prizm 2 DR. The company has said that units manufactured after that date have not short-circuited.
But Guidant officials have yet to describe what steps they took in 2002, if any, to determine if the Contak Renewal was also prone to short-circuiting. The Contak Renewal was under review that year by the F.D.A., which approved its sale in December 2002.
In both the Prizm 2 and Contak Renewal, Guidant used polyimide to insulate wiring within a component that sits atop the hermetically sealed portion of a heart device. That component contains the unit’s battery and computer chip. Guidant’s major competitors, Medtronic and St. Jude Medical, only use polyimide inside the sealed portion of a device where, engineers say, the material is not vulnerable to deterioration from exposure to moisture like bodily fluids.
Guidant changed how it manufactured the Contak Renewal and Contak Renewal 2 in August 2004. The company said that it did not notify doctors about problems in those devices and the Prizm 2 DR earlier because the number of failures involving the units did not exceed company expectations.
Last month, the Justice Department subpoenaed records about polyimide from Accellent, a company that supplied materials to Guidant. Julie Zawisza, a spokeswoman for the F.D.A., said yesterday that the agency’s investigation into Guidant was continuing.