How to Place a Lead in the Azygos Vein

Failed defibrillation during defibrillation threshold (DFT) testing of an implantable cardioverter-defibrillator (ICD) is rare with modern systems. However, when failed defibrillation occurs, implanting physicians must understand techniques to increase clinical success. One option is programming optimization such changing the shocking vector or the defibrillation pulse profile (tilt). If initial programming changes are unsuccessful, consideration can be given for RV lead revision, with a more apical lead position and/or the ICD generator can be placed in a submuscular position to modify the shocking impedance. Other available options include addition of a subcutaneous array or epicardial patch. Azygos vein coil implantation has been described as an alternative technique to optimize DFTs. Placement of a shocking coil in the azygos vein, posterior to the heart, allows for an improved shocking vector that includes more of the left ventricular myocardium. In this chapter we discuss the techniques for implantation of an azygos vein lead to improve ICD shocking vector and lower DFTs.