Computer modelling of misdiagnosis of atrial fibrillation as ventricular tachycardia by algorithms used in the implantable defibrillator

Inappropriate detection of atrial fibrillation as ventricular tachycardia by the implantable cardioverter defibrillator (ICD) may result in the delivery of painful shock therapies or potentially proarrhythmic antitachycardia pacing therapies. A computer model of three different contemporary ICDs was used to examine their susceptibility to atrial fibrillation. For any given programmed tachycardia detection interval (TDI) an algorithm requiring all R-R intervals to be shorter than TDI is less likely to be satisfied by spontaneously occurring atrial fibrillation than one which requires only a proportion of R-R intervals to be shorter than the TDI. This difference is most marked at longer TDIs