Ablation of a symptomatic spontaneous automatic focus arising from an atriofascicular fiber

Multiple QRS Morphologies

Regular wide complex tachycardia carries with it a standard array of differential diagnoses. This electrocardiogram demonstrates wide complex tachycardia and multiple QRS configurations in a neonate without structural heart disease with an uncommon suspected underlying diagnosis. (Level of Difficulty: Advanced.)

An unusual ectopic ventricular rhythm in a young woman

A case of a 22-year-old young pregnant woman with palpitations and near syncope is presented. Holter monitoring showed very frequent premature beats and runs of wide complex tachycardia, refractory to antiarrhythmic drugs. Electrophysiologic evaluation disclosed spontaneous automatism arising in an atriofascicular pathway. Differential diagnosis is discussed.