A 72-year-old man with a history of non-ischaemic cardiomyopathy in New York Heart Association III with an ejection fraction of 30% after optimized medical therapy. He underwent implantation of an implantable cardioverter-defibrillator (ICD) for primary prevention with dual-coil, passive fixation ventricular lead (Riata ST Optim™ Model 7070). Two years after implantation, the patient presented to hospital with infected defibrillator requiring defibrillator explantation.
After ICD removal, the ventricular lead was examined and showed evidence of conductor externalization just proximal to the distal coil (panel A) over a 1 cm length. We then carefully reviewed the chest X-ray and found evidence of conductor externalization (panel B).
Externalization of cables in the Riata and Riata ST leads has been reported. Optim™ coating was developed to prevent lead–lead abrasion. Inside-out abrasion of the silicone insulation, resulting in externalization of cables in the Riata and Riata ST leads has been reported.
The 7070 Riata lead has an Optim™ overlay that ends 1cm proximal to the distal coil. We observed cable externalization only in the silicone-insulated segment of the lead. This could be good news for limiting externalization. However, this issue is not resolved and careful surveillance should be emphasized.
The full-length version of this report can be viewed at: http://www.escardio.org/communities/EHRA/publications/ep-case-reports/Documents/Conductor-externalization.pdf
