Externalized conductor of a Kentrox lead and an unexpected insulation failure

Cardiac resynchronization therapy-defibrillator device upgrades may represent a challenging scenario, especially because unexpected findings can increase procedure difficulty. One such unexpected finding represents insulation failure with unremarkable device interrogation. Insulation failure due to an externalized conductor of an implantable cardiac defibrillator-lead has been recently described for the Kentrox lead (Biotronik). Another challenging aspect of device upgrades is the presence of venous thrombosis as in this case. Here, we report an inside-out abrasion of a Kentrox lead, an unexpected second insulation failure found during pocket revision and the successful recanalization in a patient with known left subclavian vein thrombosis.