Handheld ECG in analysis of arrhythmia and heart rate variability in children with Fontan circulation

BackgroundOur aim was to evaluate the intermittent use of a handheld ECG system for detecting silent arrhythmias and cardiac autonomic dysfunction in children with univentricular hearts.MethodsTwenty-seven patients performed intermittent ECG recordings with handheld devices during a 14-day period. A manual arrhythmia analysis was performed. We analyzed heart rate variability (HRV) using scatter plots of all interbeat intervals (Poincaré plots) from the total observation period. Reference values of HRV indices were determined from Holter-ECGs in 41 healthy children.ResultsOne asymptomatic patient had frequent ventricular extra systoles. Another patient had episodes with supraventricular tachycardia (with concomitant palpitations). Seven patients showed reduced HRV.ConclusionsAsymptomatic arrhythmia was detected in one patient. The proposed method for pooling of intermittent recordings from handheld or similar devices may be used for detection of arrhythmias as well as for cardiac autonomic dysfunction.