Ajmaline Challenge

The purpose of the Ajmaline Challenge is to diagnose Brugada Syndrome.

The preparation of Ajmaline should be 1mg/kg into a 20 ml syringe.  Maximum dose is 100 mg.   The administration of the drug should be at a slow IV injection 5-10 mg per minute.

ECG protocol:

  1. Perform a 12 lead ECG at baseline with leads V1 and V2 in the conventional 4th ICS and then repeat with V1 and V2 in the 3rd ICS.
  2. Perform 12 lead 5, 10, 15, 20, 30, 40, 50 and 60 minutes after the injection us started with V1 and V2 in the 3rd ICS. Mark the timing and V1/V2 positions on the ECG
  3. Stop the infusion if obvious Type 1 Brugada pattern appears or ventricular arrhythmias are seen.
  4. Monitor until the ECG has normalized.

Positive test:

In case of a negative baseline ECG, a J – wave amplitude of <2 mm absolute amplitude in lead V1 and/or V2 and/or V3 with or without RBBB is considered positive.  Conversion of a type 2 or 3 ECG to type 1 is considered positive.  An increase in the J wave amplitude of more than 2 mm without the development of a type 1 configuration is also considered significant but is rarely observed.

If ventricular arrhythmias are observed, treatment is with intravenous isoprenaline (isoproterenol) infusion and magnesium.