Outcome of the Fidelis implantable cardioverter-defibrillator lead advisory: a report from the Canadian Heart Rhythm Society Device Advisory Committee.
BACKGROUND
The Medtronic Sprint Fidelis family of leads has recently been the subject of a widespread advisory. Lead failure rates are estimated at 2.3% at 30 months, 2.6 times the failure rate of the reference Medtronic 6947 lead.


OBJECTIVE
The purpose of this study was to contact pediatric and adult implantable cardioverter-defibrillator (ICD) implant centers across Canada to determine the short-term response to the October 15, 2007 Medtronic Fidelis lead advisory.


METHODS
All centers completed an 11-part survey to assess the frequency and presentation of lead failure, operator characteristics, and center's response.


RESULTS
Lead failure was noted in 80 (1.29%) of 6,181 patients at 21.0 months, with inappropriate shocks experienced in 45 (56%) of the 80 patients (overall risk 0.73%). No deaths were attributed to lead failure. Sensing was the primary form of failure, seen in 60 leads (75%), with pacing failure in 10 (13%), and high-voltage failure in 15 (19%). Assessment of the previous routine ICD interrogation prior to the advisory or lead failure demonstrated evidence of altered lead performance in only 8 (10%) of the 80 leads. Inappropriate shocks typically were multiple (median 7, range 1-122), with a single shock seen in only 5 patients. Lead failure was noted in 18 of 23 centers, representing 89.8% of leads implanted, with at least one failure noted in 15 of 16 centers that implanted more than 200 leads. Forty-seven of the 135 operators in the 23 institutions implanted the 80 leads that subsequently failed. Only 16 operators were involved in more than a single lead that subsequently failed; seven operators participated in three or more leads that subsequently failed. Seven centers planned to replace leads in most pacing-dependent patients, and two centers planned to replace leads in patients unable to hear the alert tone.


CONCLUSIONS
This national experience suggests a Fidelis lead failure rate of 1.29% at 21 months, most often presenting with multiple inappropriate shocks without evidence of impending failure from routine lead follow-up. Lead failure did not appear to cluster around specific operators or around high-volume or low-volume implant centers.
Krahn
Andrew D
AD
London Health Sciences Center, University Campus, 339 Windermere Road, London, Ontario, Canada N6A 5A5. akrahn@uwo.ca
Champagne
Jean
J
Healey
Jeffrey S
JS
Cameron
Doug
D
Simpson
Christopher S
CS
Thibault
Bernard
B
Mangat
Iqwal
I
Tung
Stanley
S
Sterns
Laurence
L
Birnie
David H
DH
Exner
Derek V
DV
Parkash
Ratika
R
Sivakumaran
Soori
S
Davies
Ted
T
Coutu
Benoit
B
Crystal
Eugene
E
Wolfe
Kevin
K
Verma
Atul
A
Stephenson
Elizabeth A
EA
Sanatani
Shubhayan
S
Gow
Robert
R
Connors
Sean
S
Paredes
Felix Ayala
FA
Essebag
Vidal
V
D026683:Advisory Committees; D002170:Canada; D017147:Defibrillators, Implantable; D004868:Equipment Failure / Q000706:statistics & numerical data; D006306:Health Surveys; D006801:Humans; D012955:Societies, Medical