Shock vector modulation via axillary vein coil in a right-sided implantable cardioverter-defibrillator

In the early years of implantable cardioverter-defibrillator (ICD) placement, defibrillation threshold (DFT) testing was often routinely performed at the time of the initial implantation.1 Subsequent randomized clinical trials comparing routine DFT testing to omission of DFT testing at implantation showed no clinical difference in the efficacy of subsequent appropriate ICD shocks, arrhythmic death, and all-cause mortality.2,3 Given this evidence, routine DFT testing is no longer recommended and is rarely performed clinically except in special circumstances.