Superelastic Conductor Material with Enhanced Fatigue Durability for Implantable Lead Service

Abstract Advances is lead materials can spur advances in patient care. Rune Elmqvist’s pacemaker was delivered by Dr. Åke Senning into Arne Larsson in 1958 using stainless steel. Arne received 25 additional pacemakers until his death in 2001. In Arne’s 86 years of life, he experienced fracture of early stainless-steel leads and lived through the advent of Elema-Ericsson’s ribbon-based coiled conductors, the advance of more durable CoNiCrMo-leads, and advanced designs using silver-core composite wires in the 1980’s and 1990’s. Classic steel leads, while beneficial to patients, also came with fracture complications and multiple percentage fatality. Clinician signals for improvement were taken up by engineers developing helical conductors that reduced cyclic material stresses, brazed composites that improved fatigue damage resistance, 35N LT alloy, and composite wires that improved electromechanical performance. The aim of this study was to demonstrate the feasibility and performance of nitinol-based wire constructs for lead design.