Emergency in False-Electrical Storm in Patients with Implanted Cardioverter Defibrillator

The Electrical Storm (ES) indicates cardiac electrical instability manifested by several episodes of ventricular tachyarrhythmias within a short time. False-ES is defined as recurrent inappropriate Implantable Cardioverter-Defibrillator (ICD) discharges over 24 hours. Far from being a minor complication, False-ES is usually physical and psychological harmful and potentially lethal. The most common causes of inappropriate ICD shock include supraventricular tachycardia with high ventricular response and oversening of peaked T waves or R wave, myopotentials or electrical noise. Appropriate diagnosis and treatment are critical in Emergency Department. To approach these patients systematically, it is important to understand that in general, there are four causes of shock. Modern ICD incorporate sophisticated tachycardia detection algorithms within their programming designed to minimize detection mistakes by the device and ICD-related information can also be checked using remote home monitoring systems. They are often not utilized to their full benefit. Thus, careful attention should be paid to the programming of the device. Fine tuning of the detection and differentiation algorithms is critical, and best done by a practitioner who understands the subtle differences among the different manufacturers. The approach to this problems is reviewed.