Long QT Syndrome


Step 1: View clinicals

A 21 year old woman is brought in 25 minutes after experiencing dizziness and a fluttering feeling in her chest. ECG monitoring by the first responders revealed a polymorphic ventricular tachycardia, which subsided spontaneously. The entire episode lasted around 10 minutes. She experienced 2 similar episodes over the last 3 days, although none were are as severe. All of them lasted for a couple of minutes at most. She is 2 weeks postpartum, having delivered a healthy baby boy vaginally, following an uncomplicated pregnancy. Her medical, surgical, and family histories are completely unremarkable, and she is not on any medications. She does not drink or smoke.

Step 2: Order all relevant investigations


The ECG is in sinus rhythm, with a rate of 85 bpm. The P wave, and QRS complex are morphologically normal, but in all leads, the T waves are of low amplitude. No U waves are seen. The PR interval is of normal length, while the QT interval is 420 milliseconds. Serial ECGs reveal no dynamic changes.

Serum Electrolytes

Serum levels of Na+, K+, Cl-, Ca++, and Mg++ are all within normal parameters.


There are no structural or valvular lesions, or wall motion abnormalities. The ejection fraction is >70%.

MRI Brain

The MRI scan of the Brain reveals no abnormalities.

Step 3: Select appropriate management

Beta Blockers
Screen Family Members
ICD Implantation

Score: ★★☆