Answers for ECG case for the 17th of January 2024

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This ECG represents fever induced Brugada syndrome.

Needs aggressive treatment of the fever and Cardiology referral for ICD.

Additional information from LITFL:

Brugada Syndrome Key Points

  • There’s really only one type of Brugada syndrome.
  • Diagnosis depends on a characteristic ECG finding AND clinical criteria.
  • Further risk stratification is controversial.
  • Definitive treatment = ICD.
  • Brugada sign in isolation is of questionable significance.

Aetiology of Brugada Syndrome

In a nutshell, Brugada syndrome is due to a mutation in the cardiac sodium channel gene. This is often referred to as a sodium channelopathy. Over 60 different mutations have been described so far and at least 50% are spontaneous mutations, but familial clustering and autosomal dominant inheritance has been demonstrated.

ECG changes can be transient with Brugada syndrome and can also be unmasked or augmented by multiple factors:

  • Fever
  • Ischaemia
  • Multiple Drugs
    • Sodium channel blockers eg: Flecainide, Propafenone
    • Calcium channel blockers
    • Alpha agonists
    • Beta Blockers
    • Nitrates
    • Cholinergic stimulation
    • Cocaine
    • Alcohol
  • Hypokalaemia
  • Hyperkalaemia
  • Hypothermia
  • Post DC cardioversion

Diagnostic Criteria

Type 1

  • Coved ST segment elevation >2mm in >1 of V1-V3 followed by a negative T wave.
  • This is the only ECG abnormality that is potentially
  • It is often referred to as Brugada sign.

This ECG abnormality must be associated with one of the following clinical criteria to make the diagnosis:/ Shanghai criteria/

  • Documented ventricular fibrillation (VF) or polymorphic ventricular tachycardia (VT).
  • Family history of sudden cardiac death at <45 years old .
  • Coved-type ECGs in family members.
  • Inducibility of VT with programmed electrical stimulation .
  • Nocturnal agonal respiration.

The other two types of Brugada are non-diagnostic but possibly warrant further investigation (see discussion below).

Type 2

  • Brugada Type 2has >2mm of saddleback shaped ST elevation.

Type 3

  • Brugada type 3:can be the morphology of either type 1 or type 2, but with <2mm of ST segment elevation.

Management

The only proven therapy is an implantable cardioverter – defibrillator (ICD). Quinidine has been proposed as an alternative in settings where ICD’s are unavailable or where they would be inappropriate (eg: neonates).

Undiagnosed, Brugada syndrome has been estimated to have a mortality of 10% per year.

Svetlana Trandos