Medtronic and FDA notified healthcare professionals and patients of a Class I recall of Medtronic Kappa Series 600/700/900 and Sigma Series 100/200/300 pacemakers due to a failure of the devices to pace the heart. Patients with malfunctioning pacemakers may experience a return of symptoms associated with abnormal heart rate, such as fainting or lightheadedness. In rare cases, pacemaker-dependent patients may experience serious injury or even death. These devices may fail due to a separation of wires that connect the electronic circuit to other pacemaker components, such as the battery. Most of the pacemakers affected by this recall have been implanted in patients for five years or longer. To determine if a pacemaker is part of this recall, contact Medtronic at 1-800-505-4636. More details are available on the FDA Web site.