INCREASED DISPERSION OF ATRIAL REFRACTORINESS PREDICTS MOST OF THE INAPPROPRIATE IMPLANTABLE CARDIOVERTER-DEFIBRILLATOR SHOCKS

Background and aim: Despite the proven survival benefits of implantable cardioverter-defibrillators, inappropriate shocks limits their benefits due to adverse effects on quality of life, potential arrhythmogenesis an deven on mortality. Atrial fibrillation (AF) is the most common cause of inappropriate shocks. Therefore, to predict and treat AF may prevent inappropriate shocks and their hazardous potentials. This paper aimed to show that by measuring atrial refractoriness, we could predict the patients who may experience inappropriate implantable cardioverter-defibrillator shocks.\n Material and methods: 186 consecutive patients who underwent initial ICD implantation underwent coronary angiography and also underwent electrophysiologic (EP) study before the ICD implantation. \nResults: Of 169 patients who could be followed, 34 received (20%) at least 1 inappropriate shocks during the mean follow-up of 30 months. Majority of these shocks were due to AF (68%). Atrial effective refactory periods (AERPs) and AERP dispersion were the most significant predictors for these inappropriate shocks. \nConclusion: We found that simple EP study parameters measuring atrial refractoriness may define the patients carrying higher risk for future inappropriate shocks due to AF. In these patients, by either device programming or pharmocological treatments or ablation procedures, we could prevent inappropriate shocks and their hazardous results.