Cardiac Arrhythmias And Conduction Disorders Practice Test

A 28-year-old woman presents to the emergency department with a 2-hour history of sudden-onset palpitations and lightheadedness. She has no significant past medical history. Her temperature is 37.0°C (98.6°F), blood pressure is 115/75 mm Hg, pulse is 170/min and regular, and respirations are 18/min. The physical examination is unremarkable. An ECG reveals a regular, narrow-complex tachycardia with no discernible P waves.

A 24-year-old graduate student presents to the urgent care clinic with palpitations that started abruptly one hour ago. She feels anxious but is not experiencing chest pain, dyspnea, or syncope. Her blood pressure is 120/80 mm Hg and her heart rate is 160/min. An ECG shows a regular, narrow-complex tachycardia. She is alert and oriented.