Significance of automated external defibrillator in identifying lethal ventricular arrhythmias

Automated electrical defibrillator (AED) is critical in saving children who develop unexpected cardiac arrest (CA), but its diagnostic capacity is not fully acknowledged. Retrospective cohort study of patients with aborted sudden cardiac death (SCD) was performed. Twenty-five patients (14 males) aged 1.3 to 17.5 years who presented with CA survived with prompt cardiopulmonary resuscitation. Eighteen patients had no prior cardiac diagnosis. Cardiac arrest occurred in 10 patients with more than moderate exercise, in 7 with light exercise, and in 8 at rest (including one during sleep). Twenty-two patients were resuscitated with AED, all of which were recognized as a shockable cardiac rhythm. Thorough investigations revealed 6 ion channelopathies (4 catecholaminergic polymorphic ventricular tachycardia, one long QT syndrome, and one Brugada syndrome), 5 congenital heart disease (including 2 with coronary artery obstruction), 6 cardiomyopathies, 2 myocarditis, and 2 miscellaneous. Four patients had no identifiable heart disease. In 5 patients, the downloaded AED-recorded rhythm strip delineated the underlying arrhythmias and their responses to electrical shocks. Four patients who presented with generalized seizure at rest were initially managed for seizure disorder until AED recording identified lethal ventricular arrhythmias.

Conclusions: AED reliably identifies the underlying lethal ventricular arrhythmias in addition to aborting SCD.