Is defibrillation testing necessary?

With advancements in implantable cardioverter defibrillator (ICD) technology, the practice of performing defibrillation threshold (DFT) testing at the time of implantation has been questioned. With availability of biphasic waveforms, active cans, and high-output devices, opponents claim that DFT testing is no longer necessary. Clinical trials demonstrating the efficacy of ICDs in prevention of sudden cardiac death have, however, all used some form of defibrillation testing. This debate is fueled by the absence of data from randomized prospective trials evaluating the role of DFT testing in predicting clinical shock efficacy or survival. This review discusses both sides of the argument.