title: Thin co-radial bipolar leads: technology and clinical performance.
abstract: While bipolar leads offer advantages such as better sensing performance than unipolar leads, their use has been limited by a larger lead diameter and reports about a high failure rate of several bipolar lead models. This has led to the development of thin bipolar leads using a special technology which aims at improving lead safety. Leads with monofilar thin conductors (drawn filled tube) which are individually coated with a very resistant material (ETFE) have been developed. Using a co-radial instead of co-axial bipolar conductor design, the lead diameter could be reduced to 4.5 F compared to 6-7 F of conventional bipolar leads. Bench testing demonstrated a significant improvement of this lead technology with respect to degradation of insulation material by biochemically reactive solutions. Also mechanical characteristics such as resistance to tearing forces and compression showed a high lead durability. From our own experience, co-radial bipolar leads show a favorable electrical performance with the exception of a relatively low pacing impedance. Also during long-term follow-up, the rate of lead failure was very low. These findings are corroborated by other clinical studies which also demonstrated good handling characteristics of thin bipolar leads during implantation.
authors.affiliation: Department of Cardiothoracic Surgery University Hospital of Lund, Sweden, Sweden.
authors.forename: T
authors.initials: T
authors.lastname: Fahraeus
authors.affiliation: J.W. Goethe University Hospital Department of Medicine - Division of Cardiology Theodor-Stern-Kai 7 60590 Frankfurt, Germany Tel.: +49-69/6301-0 Fax: +49-69/6301-6341 E-Mail: C.W.Israel@em.uni-frankfurt.de, Germany.
authors.forename: C W
authors.initials: CW
authors.lastname: Israel
authors.affiliation: Guidant Co., Brussels, Belgium, Belgium.
authors.forename: M
authors.initials: M
authors.lastname: Wöllenstein
keywords: Key words Pacemaker leads; bipolar leads; conductors; insulation material; lead technology