Clinical introduction

A 50-year-old woman with recurrent episodic palpitations presented with hypotension to the emergency department. Her past medical history was inconsequential other than the use of β-blockers for occasional palpitations. A 12-lead surface ECG was taken (figure 1A) and the patient was subsequently cardioverted with 200 J to sinus rhythm (figure 1B). Her biochemical investigations and transthoracic echocardiogram were within normal limits.

Question

Identify the tachycardia and findings in post-cardioversion sinus rhythm ECG (figure 1)?

1. Ventricular tachycardia and sinus rhythm with right bundle branch block

2. Ventricular tachycardia and sinus rhythm showing inferior wall myocardial infarction

3. Antidromic tachycardia and pre-excitation with left accessory pathway

4. Pre-excited atrial fibrillation and …