DISCUSSION:
Brugada syndrome is an inherited sodium channel defect that gives rise to fatal ventricular arrhythmia and sudden death(5). Brugada disease is an autosomal dominant inherited disease that runs in families, however, more than 60% of cases are sporadic. The gene involved is SCN5A which encodes the alpha portion of the sodium channels in cardiac muscles. (6) There’s not enough evidence to connect this disease with structural changes in the heart (5).
There are 3 types of Brugada Syndrome, which differ in their ECG presentation. Only type 1, when present is considered a diagnostic criterion, whereas the other 2 are suggestive of the disease rather than diagnostic(7). Type 1 is characterized by ST-segment elevation ≥2 mm in more than 1 lead in the pericardial leads ( V1, V2, V3) followed with T inversion (8). Type 2 is the same ST elevation criteria but followed by biphasic or normal T wave, and Type 3 where ST elevation is ≤1 mm(9).
Brugada syndrome can be considered as a differential diagnosis when there is a family history, previous cardiac arrhythmia, previous syncope, previous ventricular tachycardia or fibrillation (10).
To diagnose Brugada syndrome a new scoring system was made, namely the Shanghai Score System which was built on the previous clinical research and data available(11). This score takes into consideration the ECG Changes, past medical history, genetics, and family history. If the score is 2-3 , Brugada is a possible diagnosis, if the score is ≥3.5 it’s a definite diagnosis(12).
The Proposed Shanghai Score System for diagnosis of Brugada syndrome (12) -