Pulse Generator Exchange Does Not Accelerate the Rate of Electrical Failure in a Recalled Small Caliber ICD Lead.
BACKGROUND
St. Jude Riata/Riata ST defibrillator leads (St. Jude Medical, Sylmar, CA, USA) were recalled by the Food and Drug Administration in 2011 for an increased rate of failure. More than 227,000 leads were implanted and at least 79,000 patients still have active Riata leads. Studies have examined clinical predictors of lead failure in Riata leads, but none have addressed the effect of implantable cardioverter defibrillator (ICD) generator exchange on lead failure. The purpose of this study is to assess the effect of ICD generator exchange on the rate of electrical failure in the Riata lead at 1 year.


METHODS
A retrospective chart review was conducted in patients who underwent implantation of a Riata/Riata ST lead at one center. Patients with a functioning Riata lead (with/without externalized conductor) at the time of ICD exchange were compared to controls with Riata leads implanted for a comparable amount of time who did not undergo generator replacement.


RESULTS
Riata leads were implanted in 1,042 patients prior to the recall and 153 of these patients underwent generator exchange without lead replacement. Conductor externalization was noted in 21.5% of Riata leads in the ICD exchange cohort, which was not different from the control group (19.2%; P = 0.32). Two leads failed in the first year after generator replacement (1.5%) which did not significantly differ from the control group (2.0%; P = 0.57). At change-out, 54% received a commanded shock (18.6 ± 0.9 J) that did not result in any change in the high-voltage lead impedance (46.1 ± 1.1 ohms).


CONCLUSIONS
Conductor externalization was seen frequently in our cohort of patients. ICD generator exchange did not accelerate the rate of Riata lead failure at 1 year. Although both the control and the change-out cohorts failed at a rate much greater than nonrecalled leads, generator exchange did not appear to add to the problem.
From the Division of Cardiology, Emory University School of Medicine, Atlanta, Georgia.
Joshua D
JD
Lovelock
From the Division of Cardiology, Emory University School of Medicine, Atlanta, Georgia.
Ajay
A
Premkumar
From the Division of Cardiology, Emory University School of Medicine, Atlanta, Georgia.
Mathew R
MR
Levy
From the Division of Cardiology, Emory University School of Medicine, Atlanta, Georgia.
Andenet
A
Mengistu
From the Division of Cardiology, Emory University School of Medicine, Atlanta, Georgia.
Michael H
MH
Hoskins
From the Division of Cardiology, Emory University School of Medicine, Atlanta, Georgia.
Mikhael F
MF
El-Chami
From the Division of Cardiology, Emory University School of Medicine, Atlanta, Georgia.
Michael S
MS
Lloyd
From the Division of Cardiology, Emory University School of Medicine, Atlanta, Georgia.
Angel R
AR
Leon
From the Division of Cardiology, Emory University School of Medicine, Atlanta, Georgia.
Jonathan J
JJ
Langberg
From the Division of Cardiology, Emory University School of Medicine, Atlanta, Georgia.
David B
DB
Delurgio
D015331:Cohort Studies; D017147:Defibrillators, Implantable / Q000706:statistics & numerical data*; D020878:Device Removal / Q000706:statistics & numerical data*; D004567:Electrodes, Implanted / Q000706:statistics & numerical data*; D004868:Equipment Failure / Q000706:statistics & numerical data*; D005260:Female; D005845:Georgia / Q000453:epidemiology; D006801:Humans; D008297:Male; D057052:Medical Device Recalls; D008875:Middle Aged; D012189:Retrospective Studies; D018570:Risk Assessment
ICD malfunction; Riata; St. Jude; generator exchange; risk factor for ICD lead failure