Brugada syndrome is a genetic disease in the heart's electrical system with abnormal electrocardiogram (ECG) finding and an increased risk of sudden cardiac death from life-threatening arrhythmias. It is diagnosed by specific abnormalities on the ECG.

At the cellular level, tiny pores, called ion channels, on each of these cells direct the electrical activity of the heart. In the Brugada syndrome, a defect in these sodium channels causes episodes of abnormal electrical function leading to potentially fatal arrhythmias.