Narrow-complex tachyarrhythmias are rapid heart rhythms originating in the upper heart chambers, characterized by a QRS duration of less than 120 milliseconds on an EKG. These arrhythmias can be ...

A 24-year-old woman presents to the emergency department with the sole symptom of “a racing heart,” which began abruptly while she was eating dinner. She reports having had prior episodes of ...

Atrial tachycardia is a form of supraventricular tachycardia that occurs when one focus in the atria begins to fire rapidly, overwhelming the sinoatrial node. This results in rapid conduction of ...