Characteristics of Sprint Fidelis lead failure

Background. The Medtronic Sprint Fidelis ICD lead is prone to failure and the rate of failure seems to be increasing. The aim of this study was to investigate the rate of Sprint Fidelis lead failure, the characteristics, the mode of presentation and possible predictors of lead failure.Methods and Results. The rate, characteristics and presentation of Sprint Fidelis lead failure was assessed in this single-centre survey. 619 Sprint Fidelis ICD leads were implanted at our centre between December 2004 and August 2007. The mean follow-up was 32±10 (range 22–60) months; 35 patients (5.7%) required a lead re-implantation because of failure of the pace-sense conductor. Mean duration of lead survival was 23±12 (2–46) months and the rate of failure did not stabilise during follow-up. The mode of presentation was inappropriate shocks in 16 patients (45.7%), alarm alert in 12 patients (34.3%), and detection at routine follow-up in seven patients (20%). In 31 patients (89%), interrogation data revealed a sudden rise in impedance and/or frequent short VV intervals prior to lead failure and in five patients an isolated decrease of R wave (<2.5 mV). The interrogation data were not different from patients with shocks compared with patients without shocks. The interrogation data at routine follow-up in the first three months after implant were normal and stable.Conclusion. The rate of Sprint Fidelis lead failure reaches 5.7% at a mean follow-up duration of 32 months. The rate of failure does not seem to stabilise. Routine follow-up can not predict lead failure or prevent inappropriate shocks. (Neth Heart J 2010;18:12-7.)