Medical device maker Medtronic sent a letter to doctors worldwide earlier this month warning that nearly 37,000 of its Sigma and Kappa pacemakers, most manufactured between November 2000 and November 2002, could have faulty wiring that can cause the pacemakers to work improperly or not at all. This defect can be deadly for the estimated 1.7 million people who have the pacemakers implanted in their chests.
The defect involves a separation of wires that connect to the electronic circuit to the pacemaker components. Patients with the defective devices reported feeling faint or lightheaded. Medtronic has received two reports of patient deaths that may be a result of the faulty pacemakers.
An estimated 15,200 active Kappa devices and 6,100 active Sigma devices are affected by the issue. Many of the devices have been implanted in patients for five years or longer and may be nearing what Medtronic calls normal elective replacement time. Of the active Kappa and Sigma devices, Medtronic has observed 285 Kappa devices and 131 Sigma devices with the failure mechanism. The company predicts failure rates of 1.1 percent for the Kappa pacemaker and 4.8 percent for the Sigma pacemaker over the remaining lifetime of the pacemakers because of the defect.
In accordance with the HRS recommendations on device advisory communications, Medtronic will begin informing patients with registered devices that fall within the above mentioned parameters with a letter dated May 27, 2009. The letter will advise patients to contact their physician for more information.
The warning comes on the heels of a massive recall of Medtronic’s Sprint Fidelis Defibrillator leads because of reports of fractures in the leads which can result in the defibrillators to unnecessarily shock patients or fail to work altogether. To date, the Sprint Fidelis Defibrillator leads defects have been blamed on at least 13 deaths.