Cardiovascular Implantable Electronic Devices -> Leads & Electrodes: -> Technology D-PO04 - Poster Session IV (ID 15) Poster

D-PO04-112 - In-vitro Modeling Accurately Predicts Cardiac Lead Fracture At 10 Years (ID 1195)


Background: Cardiac lead conductor fatigue fracture rates vary across lead models and anatomical zones but can result in serious patient complications. Fatigue fractures are caused by repeated bending cycles due to arm movements and heartbeats. The number of bending cycles required to cause a fracture depends on the amount of curvature in the bend and the lead design. The amount of curvature in the bend depends on patient, implant, and lead design factors. Development of a predictive model has the potential to differentiate good lead designs from poor performing ones and could aid in future lead development.
Objective: To demonstrate a predictive model for lead fracture and compare to observed 10-year ICD lead fracture survival.
Methods: Lead curvature during arm and heart motion was measured in patients with previously implanted Sprint Quattro (Q) and Sprint Fidelis (F) leads. In-vitro bench testing at a range of bending levels was performed to obtain cycles to fracture data for Q and F leads. Modeled fracture survival rates for Q and F leads were obtained using Monte Carlo methods with 1,500,000 simulated patients. 10-year field survival for 3,700 patients was obtained from actively monitored post-market studies. Modeled and observed fracture survival were evaluated in extravascular and intracardiac anatomical zones.
Results: Modeled and observed fracture survival for Q (> 97%) was superior to F (< 94%), illustrated in the figure.
Conclusion: Modeled fracture survival based on in-vivo lead bending measurements and in-vitro bench testing agrees with observed field survival and can accurately discriminate lead performance.