A previously healthy 16-year-old boy is brought to the office with palpitations. He was watching a documentary in a movie theater when his heart started racing and he became dizzy. The patient claims to have experienced "rapid heartbeats" in the past and assumed they were caused by stress from school exams, but he has never experienced associated lightheadedness. He is not experiencing any chest pain or dyspnea. The physical examination is within normal parameters. The exhibit includes an ECG strip.
Which of the following is most likely to be seen in this patient?

Question

Quizplus · Accepted Answer

Eductional Objective: The Wolff-Parkinson-White (WPW) pattern is distinguished by a shorter PR interval, a wider QRS complex, and a slurred initial upstroke of the QRS complex (delta wave). It is caused by an accessory pathway that bypasses the atrioventricular node, resulting in ventricle preexcitation. Patients with the WPW pattern can develop symptomatic arrhythmias (for example, atrioventricular reentrant tachycardia) as a result of electrical impulse reentry through the accessory conduction pathway.

A Previously Healthy 16-Year-Old Boy Is Brought to the Office