Sprint Fidelis lead wires are attached to a defibrillator that is implanted internally in patients with certain heart problems. The defibrillator sends electrical shocks through the Sprint Fidelis leads in order to restore the heart’s normal rhythm.

Medtronic issued a recall of the Sprint Fidelis lead wires in October 2007 after reports emerged that the wires could fracture after they are implanted, causing a defibrillator to deliver repeated shocks to the heart. According to the consumer advocacy group Public Citizen, the Food and Drug Administration received nearly 600 reports of side effects or injuries concerning the Sprint Fidelis leads before the recall notice was issued. More than 200 of these reports involved patients who had received unnecessary shocks to the heart.

According to her lawsuit, Fisk was implanted with a defibrillator that used the Sprint Fidelis leads in January 2006. She alleges that her defibrillator delivered several shocks to her heart during several “frightening episodes” which required her to undergo additional medical care.