Inappropriate detection and therapy is the most common adverse effect of im
plantable cardioverter defibrillator therapy. One mechanism is lead artifac
t, which usually presents late and is due to stress and fatigue of the lead
components, Our experience with a defibrillator lead (Endotak Endurance EZ
leads, Models 0154/0155/0156) and its method of active fixation is describ
ed. Of 20 implants with this lead, four patients were found to have noise t
hat resulted in inappropriate detections in three. No patient received ther
apy as a consequence of these detections. The artifact appeared soon after
implant and resolved in three of four cases by 4 weeks, None of the 16 rema
ining patients developed noise after this time. This is a unique lead probl
em that resolves with time, but it may result in inappropriate therapies an
d difficult management decisions in high risk patients with ventricular arr
hythmias.