management

Last reviewed 03/2023

Any drugs which are known to prolong the QT interval should be stopped e.g. quinidine, disopyramide or sotalol.

Some recommend increasing the heart rate by pharmacological means (e.g. isoprenaline 2-10 microgrammes/minute) or by overdrive pacing.

Alternatively a safe and effective emergency treatment is intravenous administration of magnesium sulphate:

• 1- 2 g of magnesium sulphate i.v. is given over 2-3 min
  • 1-2 g is equivalent to 2-4 ml (4-8 mmol) of 50% magnesium sulphate
• a further 2 g bolus may be given if necessary
• a continuous infusion of 2-8 mg/min is commenced
• if this is ineffective then temporary ventricular pacing is indicated