BrugadaSyndrom

Brugada syndrome is a genetic disorder that predisposes to life-threatening ventricular arrhythmias and sudden cardiac death in structurally normal hearts. It is defined by a characteristic electrocardiographic pattern and typically affects middle-aged adults, with a higher prevalence in men. The condition is inherited in an autosomal dominant manner with incomplete penetrance. Mutations most often involve the SCN5A gene, which encodes a cardiac sodium channel, but there are additional possible genetic contributors and many patients have no identifiable mutation.

Diagnosis relies on electrocardiography. The hallmark is a type 1 Brugada pattern: a coved-type ST-segment elevation of at least 2 mm in the right precordial leads V1–V3 with downsloping ST segment and a negative T wave. Type 2 and Type 3 patterns (saddleback) may require pharmacologic challenge with sodium-channel blockers such as ajmaline, flecainide, or procainamide to reveal a type 1 pattern. Clinical criteria also influence diagnosis: for example, documented ventricular fibrillation or polymorphic VT, a family history of sudden cardiac death, or a history of syncope can support the diagnosis.

Clinical features include syncope or nocturnal agonal respiration, often triggered by fever or other factors that raise body temperature. Risk stratification guides management, with implantable cardioverter-defibrillator (ICD) therapy recommended for those who have survived cardiac arrest or spontaneous syncope with a type 1 pattern. Quinidine can be used as antiarrhythmic therapy in selected patients who cannot receive an ICD. Patients should avoid drugs that can provoke arrhythmias and promptly treat fever.

Epidemiology varies by population; Brugada syndrome accounts for a portion of young sudden deaths and is diagnosed more often in men, with reported regional prevalence differences.