Saint Louis University, Cardinal Glennon Children' Hospital, Pediatric Cardiology R A515, 1465 S. Grand Boulevard, St. Louis, MO 63104, USA. gfreire@slu.edu
Broad QRS rhythms (fast and slow) are worrisome findings in newborns. We present five cases with varied clinical presentations found to have broad QRS tachycardias, consistent with idioventricular rhythms. Each patient had an excellent prognosis because the tachycardias resolved, and eventually the patients were in sinus rhythm. None were symptomatic from their arrhythmia. It is important to establish the diagnosis when it occurs to differentiate this benign phenomenon from dangerous ventricular tachycardia.