title: Radiographic predictors of lead conductor fracture.
abstract: BACKGROUND
  Lead fracture is a limiting factor in high voltage lead durability. Fractures noted with the Medtronic Fidelis leads provide an opportunity to examine factors captured on implant chest x-ray that correlate with risk for lead conductor fracture. We evaluated contributory factors in a large population of fractures.
  
  
  RESULTS
  We conducted a retrospective case-control study at 8 Canadian centers that routinely capture anterior posterior and lateral chest x-rays within 2 weeks of implant. Cases were patients that experienced confirmed Medtronic Fidelis 6949 lead fracture based on standard definitions, matched one-to-one to controls for date of implant, sex, and age with normally functioning Fidelis leads from the same center. Select chart data and x-rays were collected for all patients. Radiographic measurements by ≥2 individuals per case/control were blinded to patient status. The data were analyzed using a time to failure multivariable Cox proportional hazards model with stratification for each matched pair. X-ray pairs from 111 fracture patients were compared with 111 controls (age 61.5±12.8 years, 75% male, 221 model 6949 leads). Six parameters included in the statistical analysis were significantly associated with risk of fracture, including slack/tortuosity measures, pulse generator and superior vena cava coil location, and angle of lead exit from the pocket.
  
  
  CONCLUSIONS
  Pocket, intravascular and intracardiac lead characteristics on x-ray correlate with risk of lead conductor fracture. These observations may be useful to direct implant technique to optimize lead durability. Validation in larger populations and other lead models may inform the application of these results.
authors.affiliation: From the University of British Columbia, Vancouver, British Columbia, Canada (A.D.K.); Medtronic, Minneapolis, MN (J.M., R.L., T.H., R.M.); Medtronic, Santa Ana, CA (W.W.B.); Sunnybrook and Women's Hospital, Toronto, Ontario, Canada (E.C.); Centre Hospitalier Universitaire de Sherbrooke, Sherbrooke, Quebec, Canada (F.A.-P.); University of Toronto, Toronto, Ontario, Canada (D.C.); Southlake Regional Hospital, Newmarket, Ontario, Canada (A.V.); Queen's University, Kingston, Ontario, Canada (C.S.S.); Libin Cardiovascular Institute, Calgary, Alberta, Canada (D.V.E.); and University of Ottawa Heart Institute, Ottawa, Ontario, Canada (D.H.B.). akrahn@mail.ubc.ca.
authors.forename: Andrew D
authors.initials: AD
authors.lastname: Krahn
authors.affiliation: From the University of British Columbia, Vancouver, British Columbia, Canada (A.D.K.); Medtronic, Minneapolis, MN (J.M., R.L., T.H., R.M.); Medtronic, Santa Ana, CA (W.W.B.); Sunnybrook and Women's Hospital, Toronto, Ontario, Canada (E.C.); Centre Hospitalier Universitaire de Sherbrooke, Sherbrooke, Quebec, Canada (F.A.-P.); University of Toronto, Toronto, Ontario, Canada (D.C.); Southlake Regional Hospital, Newmarket, Ontario, Canada (A.V.); Queen's University, Kingston, Ontario, Canada (C.S.S.); Libin Cardiovascular Institute, Calgary, Alberta, Canada (D.V.E.); and University of Ottawa Heart Institute, Ottawa, Ontario, Canada (D.H.B.).
authors.forename: Josée
authors.initials: J
authors.lastname: Morissette
authors.affiliation: From the University of British Columbia, Vancouver, British Columbia, Canada (A.D.K.); Medtronic, Minneapolis, MN (J.M., R.L., T.H., R.M.); Medtronic, Santa Ana, CA (W.W.B.); Sunnybrook and Women's Hospital, Toronto, Ontario, Canada (E.C.); Centre Hospitalier Universitaire de Sherbrooke, Sherbrooke, Quebec, Canada (F.A.-P.); University of Toronto, Toronto, Ontario, Canada (D.C.); Southlake Regional Hospital, Newmarket, Ontario, Canada (A.V.); Queen's University, Kingston, Ontario, Canada (C.S.S.); Libin Cardiovascular Institute, Calgary, Alberta, Canada (D.V.E.); and University of Ottawa Heart Institute, Ottawa, Ontario, Canada (D.H.B.).
authors.forename: Ryan
authors.initials: R
authors.lastname: Lahm
authors.affiliation: From the University of British Columbia, Vancouver, British Columbia, Canada (A.D.K.); Medtronic, Minneapolis, MN (J.M., R.L., T.H., R.M.); Medtronic, Santa Ana, CA (W.W.B.); Sunnybrook and Women's Hospital, Toronto, Ontario, Canada (E.C.); Centre Hospitalier Universitaire de Sherbrooke, Sherbrooke, Quebec, Canada (F.A.-P.); University of Toronto, Toronto, Ontario, Canada (D.C.); Southlake Regional Hospital, Newmarket, Ontario, Canada (A.V.); Queen's University, Kingston, Ontario, Canada (C.S.S.); Libin Cardiovascular Institute, Calgary, Alberta, Canada (D.V.E.); and University of Ottawa Heart Institute, Ottawa, Ontario, Canada (D.H.B.).
authors.forename: Tarek
authors.initials: T
authors.lastname: Haddad
authors.affiliation: From the University of British Columbia, Vancouver, British Columbia, Canada (A.D.K.); Medtronic, Minneapolis, MN (J.M., R.L., T.H., R.M.); Medtronic, Santa Ana, CA (W.W.B.); Sunnybrook and Women's Hospital, Toronto, Ontario, Canada (E.C.); Centre Hospitalier Universitaire de Sherbrooke, Sherbrooke, Quebec, Canada (F.A.-P.); University of Toronto, Toronto, Ontario, Canada (D.C.); Southlake Regional Hospital, Newmarket, Ontario, Canada (A.V.); Queen's University, Kingston, Ontario, Canada (C.S.S.); Libin Cardiovascular Institute, Calgary, Alberta, Canada (D.V.E.); and University of Ottawa Heart Institute, Ottawa, Ontario, Canada (D.H.B.).
authors.forename: Walt W
authors.initials: WW
authors.lastname: Baxter
authors.affiliation: From the University of British Columbia, Vancouver, British Columbia, Canada (A.D.K.); Medtronic, Minneapolis, MN (J.M., R.L., T.H., R.M.); Medtronic, Santa Ana, CA (W.W.B.); Sunnybrook and Women's Hospital, Toronto, Ontario, Canada (E.C.); Centre Hospitalier Universitaire de Sherbrooke, Sherbrooke, Quebec, Canada (F.A.-P.); University of Toronto, Toronto, Ontario, Canada (D.C.); Southlake Regional Hospital, Newmarket, Ontario, Canada (A.V.); Queen's University, Kingston, Ontario, Canada (C.S.S.); Libin Cardiovascular Institute, Calgary, Alberta, Canada (D.V.E.); and University of Ottawa Heart Institute, Ottawa, Ontario, Canada (D.H.B.).
authors.forename: Rick
authors.initials: R
authors.lastname: McVenes
authors.affiliation: From the University of British Columbia, Vancouver, British Columbia, Canada (A.D.K.); Medtronic, Minneapolis, MN (J.M., R.L., T.H., R.M.); Medtronic, Santa Ana, CA (W.W.B.); Sunnybrook and Women's Hospital, Toronto, Ontario, Canada (E.C.); Centre Hospitalier Universitaire de Sherbrooke, Sherbrooke, Quebec, Canada (F.A.-P.); University of Toronto, Toronto, Ontario, Canada (D.C.); Southlake Regional Hospital, Newmarket, Ontario, Canada (A.V.); Queen's University, Kingston, Ontario, Canada (C.S.S.); Libin Cardiovascular Institute, Calgary, Alberta, Canada (D.V.E.); and University of Ottawa Heart Institute, Ottawa, Ontario, Canada (D.H.B.).
authors.forename: Eugene
authors.initials: E
authors.lastname: Crystal
authors.affiliation: From the University of British Columbia, Vancouver, British Columbia, Canada (A.D.K.); Medtronic, Minneapolis, MN (J.M., R.L., T.H., R.M.); Medtronic, Santa Ana, CA (W.W.B.); Sunnybrook and Women's Hospital, Toronto, Ontario, Canada (E.C.); Centre Hospitalier Universitaire de Sherbrooke, Sherbrooke, Quebec, Canada (F.A.-P.); University of Toronto, Toronto, Ontario, Canada (D.C.); Southlake Regional Hospital, Newmarket, Ontario, Canada (A.V.); Queen's University, Kingston, Ontario, Canada (C.S.S.); Libin Cardiovascular Institute, Calgary, Alberta, Canada (D.V.E.); and University of Ottawa Heart Institute, Ottawa, Ontario, Canada (D.H.B.).
authors.forename: Félix
authors.initials: F
authors.lastname: Ayala-Paredes
authors.affiliation: From the University of British Columbia, Vancouver, British Columbia, Canada (A.D.K.); Medtronic, Minneapolis, MN (J.M., R.L., T.H., R.M.); Medtronic, Santa Ana, CA (W.W.B.); Sunnybrook and Women's Hospital, Toronto, Ontario, Canada (E.C.); Centre Hospitalier Universitaire de Sherbrooke, Sherbrooke, Quebec, Canada (F.A.-P.); University of Toronto, Toronto, Ontario, Canada (D.C.); Southlake Regional Hospital, Newmarket, Ontario, Canada (A.V.); Queen's University, Kingston, Ontario, Canada (C.S.S.); Libin Cardiovascular Institute, Calgary, Alberta, Canada (D.V.E.); and University of Ottawa Heart Institute, Ottawa, Ontario, Canada (D.H.B.).
authors.forename: Doug
authors.initials: D
authors.lastname: Cameron
authors.affiliation: From the University of British Columbia, Vancouver, British Columbia, Canada (A.D.K.); Medtronic, Minneapolis, MN (J.M., R.L., T.H., R.M.); Medtronic, Santa Ana, CA (W.W.B.); Sunnybrook and Women's Hospital, Toronto, Ontario, Canada (E.C.); Centre Hospitalier Universitaire de Sherbrooke, Sherbrooke, Quebec, Canada (F.A.-P.); University of Toronto, Toronto, Ontario, Canada (D.C.); Southlake Regional Hospital, Newmarket, Ontario, Canada (A.V.); Queen's University, Kingston, Ontario, Canada (C.S.S.); Libin Cardiovascular Institute, Calgary, Alberta, Canada (D.V.E.); and University of Ottawa Heart Institute, Ottawa, Ontario, Canada (D.H.B.).
authors.forename: Atul
authors.initials: A
authors.lastname: Verma
authors.affiliation: From the University of British Columbia, Vancouver, British Columbia, Canada (A.D.K.); Medtronic, Minneapolis, MN (J.M., R.L., T.H., R.M.); Medtronic, Santa Ana, CA (W.W.B.); Sunnybrook and Women's Hospital, Toronto, Ontario, Canada (E.C.); Centre Hospitalier Universitaire de Sherbrooke, Sherbrooke, Quebec, Canada (F.A.-P.); University of Toronto, Toronto, Ontario, Canada (D.C.); Southlake Regional Hospital, Newmarket, Ontario, Canada (A.V.); Queen's University, Kingston, Ontario, Canada (C.S.S.); Libin Cardiovascular Institute, Calgary, Alberta, Canada (D.V.E.); and University of Ottawa Heart Institute, Ottawa, Ontario, Canada (D.H.B.).
authors.forename: Christopher S
authors.initials: CS
authors.lastname: Simpson
authors.affiliation: From the University of British Columbia, Vancouver, British Columbia, Canada (A.D.K.); Medtronic, Minneapolis, MN (J.M., R.L., T.H., R.M.); Medtronic, Santa Ana, CA (W.W.B.); Sunnybrook and Women's Hospital, Toronto, Ontario, Canada (E.C.); Centre Hospitalier Universitaire de Sherbrooke, Sherbrooke, Quebec, Canada (F.A.-P.); University of Toronto, Toronto, Ontario, Canada (D.C.); Southlake Regional Hospital, Newmarket, Ontario, Canada (A.V.); Queen's University, Kingston, Ontario, Canada (C.S.S.); Libin Cardiovascular Institute, Calgary, Alberta, Canada (D.V.E.); and University of Ottawa Heart Institute, Ottawa, Ontario, Canada (D.H.B.).
authors.forename: Derek V
authors.initials: DV
authors.lastname: Exner
authors.affiliation: From the University of British Columbia, Vancouver, British Columbia, Canada (A.D.K.); Medtronic, Minneapolis, MN (J.M., R.L., T.H., R.M.); Medtronic, Santa Ana, CA (W.W.B.); Sunnybrook and Women's Hospital, Toronto, Ontario, Canada (E.C.); Centre Hospitalier Universitaire de Sherbrooke, Sherbrooke, Quebec, Canada (F.A.-P.); University of Toronto, Toronto, Ontario, Canada (D.C.); Southlake Regional Hospital, Newmarket, Ontario, Canada (A.V.); Queen's University, Kingston, Ontario, Canada (C.S.S.); Libin Cardiovascular Institute, Calgary, Alberta, Canada (D.V.E.); and University of Ottawa Heart Institute, Ottawa, Ontario, Canada (D.H.B.).
authors.forename: David H
authors.initials: DH
authors.lastname: Birnie
mesh_terms: D000368:Aged; D002170:Canada; D017147:Defibrillators, Implantable; D004554:Electric Countershock / Q000009:adverse effects / Q000295:instrumentation*; D004867:Equipment Design; D004868:Equipment Failure; D019544:Equipment Failure Analysis; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011237:Predictive Value of Tests; D016016:Proportional Hazards Models; D013902:Radiography, Thoracic; D012189:Retrospective Studies; D013997:Time Factors
keywords: defibrillators, implantable; radiography