Due to high failure rates, Medtronic withdrew the Sprint Fidelis
lead (SFL) from the market. Passive fixation lead models exhibited
better survival than active models, but most studies have limited
follow-up. Aim of this study was to give insights into passive lead
survival with a follow-up of 10 years.
In two large Swiss centers, patients with passive SFLs were
identified and data from routine implantable cardioverter
defibrillator (ICD) follow-ups were collected. Patients were
censored at time of death, last device interrogation (if lost to
follow-up), time of lead revision (in non-SFL-related problems), or
at database closure (31th December 2017). We defined lead failure as
any of the following: lead fracture with inappropriate discharge;
sudden increase in low-voltage impedance to >1500 or
high-voltage impedance to >100 Ω; >300
nonphysiological short VV-intervals.
We identified 145 patients. Age at implant was
60 ± 12 years with a median follow-up of 10.2
(interquartile range [IQR]: 5.0-11.2) years. Thirty-five percent of
patients died after 5.4 ± 2.7 years. A total of 19
leads (13%) failed after 6.7 ± 3.2 years (range:
1.2-12.0). Overt malfunction with shocks existed in four patients
(3%). Cumulative lead survival was 93.1% at 6, 88.2% at 8, 83.8% at
10, and 77.6% at 11 years, respectively, with 35% of implanted leads
under monitoring at 10 years. Lead survival fits best a Weibull
distribution with accelerating failure rates (k = 1.95,
95% CI 1.32-2.87, P < 0.001).
During very long-term follow-up, failure rate of the passive SFL
shows an increase resulting in an impaired lead survival of 84% at
Frey S M, Sticherling C, Altmann D, Brenner R, Kühne M, Ammann P,
Coslovsky M, Osswald S, Schaer B. The Medtronic Sprint Fidelis®
lead history revisited-Extended follow-up of passive leads. Pacing
Clin Electrophysiol 2019;.