Predictors of fracture risk of a small caliber implantable cardioverter defibrillator lead.
BACKGROUND
The Sprint Fidelis 6949 implantable cardioverter defibrillator (ICD; Medtronic Inc., Minneapolis, MN, USA) lead has a high rate of fracture. Identification of predictors of subsequent fracture is useful in decision making about lead replacement and for future lead design. We sought to determine if there are clinical, procedural, or radiological features associated with a greater risk of subsequent lead fracture.


METHODS
Patients with Sprint Fidelis 6949 lead fractures (Fracture group) were identified from our institutional database. Each patient in the Fracture group was matched to two controls, immediately preceeding and succeeding Sprint Fidelis 6949 implant. Clinical and procedural characteristics were compared. Chest radiographs performed 2 weeks after ICD implant were reviewed by an observer blinded to outcomes. The following features were assessed: ICD tip location, lead slack, kinking of the lead body (> or =90 degrees ), and presence of lead "crimping" within the anchoring sleeve.


RESULTS
Twenty-six patients with Sprint Fidelis 6949 lead fractures were identified and were matched to 52 control patients. On univariate analysis, a higher left ventricular ejection fraction (LVEF), prior ipsilateral device implant, history of prior ICD lead fracture, and noncephalic venous access were associated with risk of lead fracture. On multivariate analysis, a higher LVEF was the only independent predictor of lead fracture (P = 0.006). Radiological features were similar between the two groups.


CONCLUSIONS
In this study, a higher LVEF was associated with a greater risk of lead fracture in patients with Sprint Fidelis 6949 ICD leads. Radiographic features did not predict subsequent risk of lead fracture in our population. (PACE 2010; 437-443).
Ha
Andrew C T
AC
University of Ottawa Heart Institute, Ottawa, Ontario, Canada.
Vezi
Brian Z
BZ
Keren
Arieh
A
Alanazi
Haitham
H
Gollob
Michael H
MH
Green
Martin S
MS
Lemery
Robert
R
Nery
Pablo B
PB
Posan
Emoke
E
Birnie
David H
DH
D000368:Aged; D017147:Defibrillators, Implantable; D004567:Electrodes, Implanted; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011475:Prosthesis Failure; D013902:Radiography, Thoracic; D012307:Risk Factors