A Medical Device Daily

Boston Scientific (Natick, Massachusetts) reported that it has notified doctors that some of its implantable heart defibrillators contain batteries that could deplete early, shortening the life span of the devices.

The company said in its letter, dated last Thursday and posted on the web site of its Guidant unit, that there have been no patient deaths or serious injuries associated with the battery voltage problem.

Accelerated battery depletion was found to have occurred in 19 of about 73,000 devices in the Vitality family of implantable cardioverter defibrillators, which restore heart rhythms, and the Contak Renewal line of cardiac resynchronization therapy devices.

Boston Scientific bought Guidant last year for $27 billion primarily to acquire its portfolio of heart rhythm management devices. But high-profile recalls of some of the devices have depressed sales. More than 100,000 Guidant heart rhythm devices were recalled between 2005 and 2006.

Bear Stearns analyst Rick Wise, wrote in a research note that he considers the development an "incremental negative" for Boston Scientific. "While we are not sure if this capacitor issue is related to past capacitor issues, or if the incidence of 19/73,000 ICDs with the known issue will increase, the additional vigilance required for doctors and patients to monitor this issue puts Boston Scientific products in a negative light."

In its letter to doctors, Boston Scientific estimated that fewer than 2% of the devices identified were at risk for early battery depletion. The average implantable defibrillator lasts five to seven years.

The firm provided guidelines for identifying which patients have devices with faulty batteries and recommended monitoring them every month instead of the usual three months.