Clinical Predictors of Fidelis Lead Failure: A Report from the Canadian Heart Rhythm Society Device Committee
Background—Approximately 268 000 Fidelis leads were implanted world-wide until distribution was suspended due to a high rate of early failure. Careful analyses of predictors of increased lead failure hazard are required to help direct future lead design, and also to inform decision making on lead replacement. We sought to perform a comprehensive analysis of all potential predictors in a multi-center study.
Methods and Results—A total of 3169 Sprint Fidelis leads were implanted in eleven centers with a total of 251 failures. Three, four and five year lead failure rates were 5.3%, 10.6% and 16.8%. The rate of lead failure continues to accelerate (p<0.001). There were 4 independent predictors of failure; center, gender, access vein and previous lead failure. Females had a higher hazard of failure (hazard ratio 1.51, 95% CI 1.14, 2.04, p=0.005). Both axillary and subclavian access increased the hazard of failure (p=0.007); hazard ratio for axillary was 1.94, (95% CI 1.23, 3.04), and for subclavian 1.63 (95% CI 1.08, 2.46). Previous lead failure increased the hazard of a subsequent Fidelis failure with a hazard ratio of 3.12 (95% CI 1.80, 5.41, p<0.001).
Conclusions—The rate of Fidelis failure continues to increase over time, with failures approaching 17% at 5 years. Women, patients with leads inserted via the sub-clavian or axillary vein and those with a previous lead fracture were at greatest risk of Fidelis failure. Our data suggests that Fidelis replacement should be strongly considered, at the time of generator replacement.
- Received August 4, 2011.
- Accepted January 27, 2012.
- Copyright © 2012, American Heart Association, Inc. All rights reserved. Unauthorized use prohibited