ICD Design, Not Diameter, Predictive of Lead Failure in Pediatric Patients

"What is clear from this paper is that any child that is going to get an ICD needs to be in an organized follow-up program for continuous monitoring of the device that’s been implanted," said Gerard Martin, MD, FACC.

Among pediatric patients with implantable cardioverter-defibrillators (ICD), ICD lead design may be more important than lead diameter in determining long-term ICD performance, according to a study published Oct. 16 in the Journal of the American College of Cardiology.

The retrospective analysis compared lead performance between small-diameter and standard-diameter leads implanted between January 1995 and October 2011 in 101 patients with a mean age of 15.5 ± 4.9 years. Forty-seven patients received small-diameter leads (≤8 French [Fr]) and 73 standard-diameter (>8 Fr) leads. The small-diameter Medtronic Sprint Fidelis (SF) was used in 53 percent of patients, and the St. Jude Riata, Riata ST, and Durata ICDs in 45 percent. There was one Biotronik small-diameter device. The most common standard-diameter leads were the Medtronic Spring Quattro and Sprint models (53 percent and 33 percent, respectively) and Boston Scientific’s Endotak (14 percent).

Additional Resources

The overall incidence of lead failure was 5.6 percent per year. Among those with a small-diameter lead, the rate was 12.1 percent per year versus 2.9 percent per year with standard leads. There was no statistically significant difference in failure rates between the SF and St. Jude models (SF 14.9 percent per year, 95 percent CI 6.5-23.4, and St. Jude 7.9 percent per year, 95 percent CI 0.2-15.6). However, in multivariate analysis of the individual small leads, SF design was associated with the highest risk of failure with a hazard ratio of 4.42 (95 percent CI 1.73-11.29, p = 0.002). St. Jude small-diameter devices were associated with a nonsignificant hazard ratio of 3.05 (95 percent 0.99-9.37, p = 0.052).

The investigators concluded that ICD lead failure rates are higher among pediatric than adult patients and that in this "analysis of lead diameter, lead design and patient factors, the Sprint Fidelis lead design conferred the highest risk of lead failure, suggesting that design, rather than diameter, is the critical issue in ICD lead survival. Small-diameter leads are optimal for transvenous ICD implantation in the pediatric population; therefore, research efforts should focus on re-designing a small-diameter ICD lead with enhanced durability and lead performance."

Keywords: Incidence, Multivariate Analysis, Follow-Up Studies, Cardiology, Defibrillators, Implantable, United States

< Back to Listings