Question 18.2
A 45-year-old male has been admitted to the hospital for investigation of syncope. He has a MET call for another syncopal episode. His 12 lead ECG is shown below (ECG 2).
a) Describe the ECG changes.
b) What is the most likely diagnosis?
c) What is the underlying pathophysiology?
d) List four clinical situations that can worsen this condition.
College Answer
a)
Coved ST segment elevation V1 – V2 > 2 mm.
Subsequent negative T wave in the same leads.
b)
Brugada syndrome (Type 1).
c)
A mutation in the cardiac sodium channel gene.
d)
Fever.
Myocardial ischaemia.
Medications
o E.g. Flecainide, Amitriptyline, Lithium, Bupivacaine, Propofol, Alcohol.
Hypokalaemia.
Hypothermia.
Cardioversion.
Discussion
The criteria for the diagnosis of Brugada syndrome as well as are explored to a fascinating depth by Edward Burns in his article for LITFL. The time-poor exam candidate will be interested in only the answers to this question:
Clinical criteria:
- Characteristic ECG changes
- "Coved" ST elevation: the QRS complex finishes high, and the ST-segment slopes diagonally to form an inverted T-wave in V1 and V2
- Inverted T waves
- Also, one of the following:
- documented polymorphic VT or VF
- Family history of sudden cardiac death before the age of 45
- Characteristic ECG changes in family members
- Syncope
- Induceable VT
- Nocturnal agonal respiration
Clinical situations which can worsen this condition:
- Ischameia
- Hyperthermia or hypothermia
- Hypokalemia
- Cardioversion
- Drugs:
- Class 1 antiarrhythmics
- Beta blockers and calcium channel blockers
- Alpha-agonists
- Nitrates
- Cocaine and alcohol
- Cholinergic agonists, eg. the "stigmine" drugs
References
Berne, Paola, and Josep Brugada. "Brugada syndrome 2012." Circulation Journal 76.7 (2012): 1563-1571.