- A syndrome recognised as being a major cause of sudden cardiac death
- Patients have structurally normal hearts
- Autosomal dominant inheritance with cardiac sodium channel encoding gene SCN5A
- Predisposes patient to ventricular tachyarrhythmias
- Prevalent in Southeast Asia, particularly in Japan and Thailand.
- Higher recorded incidence in males
- Genetic distribution is equal between genders
- Present in all age groups
- Events are more common at around 40 years old
Clinical Indicators
- Syncope
- Cardiac Arrest
- Most common nocturnally
- Night Terrors
- Positive ECG criteria
- Familial history
- Symptoms can manifest after a large meal, or in the event of a fever
- AF can be an associated cause
Brugada ECG
- ST elevation in the right-side precordial leads
- Coved morphology
- RBBB or Incomplete RBBB
Diagnosis
Expect a normal physical examination; most patients with Brugada present with no symptoms.
The physical exam should be used to rule out the influence of other cardiac causes of syncope.
Perform an ECG, but bear in mind that Brugada is often transient. It may be unmasked, however, with certain methods/ under certain circumstances, for example;
- Post MI
- After a large meal
- Under pharmacological stimulation
- beta blockers
- Na channel blockers
- Cocaine
- Alcohol
- Alpha agonists
- After DC cardioversion
- Hypothermia
When gaining a 12-Lead ECG, a configuration wherein the placements of V1 and V2 are positioned more cranially (V1ICS1/2 & V2ICS1/2) should be recorded, as these leads can often give a clearer view of abnormal morphologies.
Diagnosis can only be considered appropriate with a positive ECG as well as at least one of the following;
- Proven VF or VT
- Familial history of sudden cardiac death at <45 years old
- Positive ECG criteria in family members also indicative
- Electrical induction of VT
- Syncope
- Nocturnal agonal respiration
Treatment
- Implantable Cardioverter Defibrillator
- Used in most cases
- Pharmaceuticals
- Quinidine
- Tedisamil
- Isoproterenol
- Medication effectiveness is not convincingly proved at trial level, so is often avoided.
References:
Houghton, A. Gary, D.(1997) Making Sense of the ECG Fifth edition. London: Arnold
Lilly, S. (2011) Pathophysiology of Heart Disease Fifth edition. Batimore: Lippincott Williams and Wilkins