Brugada syndrome (BrS) is a genetic disorder in which the electrical activity within the heart is abnormal.[2] It increases the risk of abnormal heart rhythms and sudden cardiac death.[2] Those affected may have episodes of passing out.[2] The abnormal heart rhythms seen in those with Brugada syndrome often occur at rest. They may be triggered by a fever. About a quarter of those with Brugada syndrome have a family member who also has the condition.[2] Some cases may be due to a new genetic mutation or certain medications.[1] The most commonly involved gene is SCN5A which encodes the cardiac sodium channel.[6] Diagnosis is typically by electrocardiogram (ECG), however, the abnormalities may not be consistently present.[2] Medications such as ajmaline may be used to reveal the ECG changes.[2] Similar ECG patterns may be seen in certain electrolyte disturbances or when the blood supply to the heart has been reduced. There is no cure for Brugada syndrome.[3] Those at higher risk of sudden cardiac death may be treated using an implantable cardioverter defibrillator (ICD).[4] In those without symptoms the risk of death is much lower, and how to treat this group is less clear.[3][8] Isoproterenol may be used in the short term for those who have frequent life-threatening abnormal heart rhythms, while quinidine may be used longer term.[3][9] Testing people's family members may be recommended.The condition affects between 1 and 30 per 10,000 people.[2] It is more common in males than females and in those of Asian descent.[1][2] The onset of symptoms is usually in adulthood