EPU Electrophysiology Practice Exam

AVNRT causes a sudden, very fast heart rhythm due to a reentrant circuit around the AV node. The rapid rate makes the heart pump less efficiently, so patients often notice palpitations along with symptoms from reduced filling and flow to the brain. The most typical presentation during an episode is a sudden onset of a fast heart rate accompanied by shortness of breath and dizziness or fainting. Chest pain on its own is not the usual feature of AVNRT, and while blood pressure can drop if the tachycardia is prolonged, this is not the defining symptom. Some people may have no symptoms between episodes, but when symptoms occur, this combination is the hallmark.