Early failure of the Biotronik Linox implantable cardioverter defibrillator lead

The Linox and Durata implantable cardioverter defibrillator (ICD) leads were introduced to British Columbia (BC) in 2008. We determined their performance and the potential risk factors for lead failure in a large population-based patient registry.

We used the BC Cardiac Registry, a mandatory Governmental database of ICD implants, to identify all recipients of Linox and Durata leads in BC between October 2008 and April 2012, and those subsequently undergoing reoperation. Lead failure was defined as recurrent nonphysiological high-rate sensing unrelated to external electromagnetic interference or T-wave oversensing; a sudden rise in impedance unrelated to perforation or lead dislodgement; or abnormal lead parameters with definite evidence of lead fracture or insulation failure. We determined the estimated cumulative lead survival by the Kaplan-Meier method, and the risk factors for lead failure in a proportional hazards model. Over a median of 39 (27-50) months, the Linox failed more frequently than the Durata (16/477 [3.4%] vs. 4/838 [0.4%]; P < 0.001), and had a significantly lower estimated cumulative survival (91.6 [80.6-96.5]% vs. 99.4 [98.4-99.8]% at 5 years; P < 0.0001). Linox failure was characterized by high-rate nonphysiological sensing (11 cases), and/or a sudden impedance rise (7 cases). Insulation failure was clearly confirmed in 6 cases of Linox failure. Female sex was a significant risk factor for Linox failure (adjusted HR = 2.1[1.3-3.4]; P = 0.004).

This multicenter registry indicates a high rate of Linox lead failure, particularly in female patients. Ongoing surveillance of the Linox ICD lead performance is recommended.