A 51-year-old woman has episodic palpitations and syncope. ECG during symptoms shows polymorphic ventricular tachycardia twisting around the

Question

A 51-year-old woman has episodic palpitations and syncope. ECG during symptoms shows polymorphic ventricular tachycardia twisting around the baseline. QTc is 540 ms. She recently started citalopram and clarithromycin and has potassium 3.0 mmol/L. What is the most likely cause?

Accepted Answer

Drug-induced QT prolongation with hypokalaemia causing torsades de pointes

Answer

Atrioventricular nodal re-entrant tachycardia

Answer

Catecholaminergic polymorphic VT

Answer

Digoxin toxicity with bidirectional VT

Answer

Acute pericarditis

Torsades de pointes — RCPSC IM MCQ

A 51-year-old woman has episodic palpitations and syncope. ECG during symptoms shows polymorphic ventricular tachycardia twisting around the baseline. QTc is 540 ms. She recently started citalopram and clarithromycin and has potassium 3.0 mmol/L. What is the most likely cause?