Is Routine Defibrillation Testing Necessary for Patients Undergoing Subcutaneous ICD Implantation?

Defibrillation testing (DFT) is recommended for all patients undergoing implantation of a subcutaneous implantable cardioverter defibrillator (S-ICD). DFT was also once recommended for patients receiving transvenous ICDs — until randomized trials showed that they were not only unnecessary but potentially harmful, after which the practice was largely abandoned. Now, investigators report long-term outcomes of DFT in a prospective French registry study including 4900 patients undergoing S-ICD implantation.

Results included the following:

• Eighty-three percent of patients received DFT.

• DFT failed in 1%, most of whom underwent corrective reintervention followed by successful DFT.

• DFT-related complications occurred in 0.1% of patients, including 2 dea…