A 73-year-old recipient of an InSync Sentry CRT-D for severe ischemic cardiomyopathy and left bundle branch block needed a pulse generator replacement for end of life of the batteries. At the end of the procedure, electrocautery was used for hemostasis while the ICD therapies were active.
During an ICD generator change it is important to 1) disable before the procedure all therapies of the pulse generator that is being removed, to prevent the delivery of a shock when using electrocautery or while removing the device, 2) likewise, wait until the end of the procedure before turning on the therapies of the new device.
Besides for implantation procedures, electrocautery may be used when a patient undergoes other surgical interventions. To avoid the overdetection of electrocautery 2 choices are available : 1) placing a magnet over the device throughout the procedure, inhibiting the therapies and preventing the storage of artifacts, or 2) temporarily programming “OFF” the detection and therapies of the ICD, which should be interrogated and reprogrammed at the end of procedure. During surgery, the patient must be monitored and external defibrillation must be immediately available, as the patient is not protected by the ICD.
The first shock is diverted due to the discontinuation of oversensing and sensing only the underlying sinus rhythm. However, the second shock is delivered as shocks cannot be aborted during redetection in older devices.
