The Brugada syndrome.

The Brugada syndrome is a hereditary disease causing sudden cardiac death in apparently healthy individuals with a structurally normal heart. The disease is caused by mutations in the cardiac sodium channel gene SCN5A. Patients with this disease have a peculiar electrocardiogram with elevation of the ST segment in leads V1 to V3, an electrocardiogram that every doctor should recognize. There exist variants of the electrocardiogram with minimal ST segment elevation and even concealed forms that can only be unmasked by the administration of class I antiarrhythmic drugs. When left untreated or when treated with all known antiarrhythmic drugs, patients with Brugada syndrome have a high mortality (approximately 10% per year). The only effective treatment to prevent sudden death is the implantable defibrillator.