The first signs of the health risks associated with the Sprint Fidelis leads came within a few years after the lead wires were released in 2004. After a large number of reports of injuries among patients wearing the lead wires began to emerge, the Minneapolis Heart Institute launched an investigation into the safety of the Sprint Fidelis leads.

The study found that the Sprint Fidelis leads have a much higher chance of fractures than the defibrillator leads they were designed to replace. Fractures in the leads can cause a defibrillator to deliver repeated, painful shocks to the heart, or can cause the device to fail to work in the event of a heart attack.

The Institute’s findings about the health risks posed by defibrillator wire problems were confirmed through an internal study conducted by Medtronic. The company’s study uncovered three times as many patients whose Sprint Fidelis leads had fractured after being implanted than with its other lead wires.

But despite the evidence of these two studies, Medtronic executives refused to issue a Sprint Fidelis lead recall, stating that the reports of fractured lead wires were not “statistically significant” and were probably caused by surgical error.

After learning of at least five deaths and more than 1,600 cases of injury or malfunction among patients using the Sprint Fidelis leads, Medtronic finally issued a Sprint Fidelis recall on October 14.

Several patients who were injured after using the Sprint Fidelis leads have filed lawsuits against Medtronic. These defibrillator recall lawsuits have alleged that Medtronic deceived customers about the safety of the Sprint Fidelis leads despite knowing the dangers associated with the lead wires.