Electrocautery has long been described to generate electromagnetic interference (EMI) and oversensing by implanted pacemakers and defibrillators. Electrocautery is commonly used during surgical procedures involving implantation and explantation of pacemakers and implantable cardioverters-defibrillator (ICDs). However, ventricular tachycardia (VT) or ventricular fibrillation (VF) occurring as a result of electrocautery has only been sporadically reported. We present 4 cases of electrocautery-associated VT or VF during either implantation or explantation of ICDs and pacemakers. The etiology of VT/VF is unclear in these circumstances. Methods This retrospective study was approved by the Institutional Review Board at Winthrop University Hospital. During the period of November 2000 to March 2006, 4,698 pacemakers and implantable defibrillators were implanted and/or explanted at Winthrop University Hospital.