[Sudden death (VI). The Brugada syndrome and right myocardiopathies as a cause of sudden death. The differences and similarities].
In 1992 we described a new syndrome characterized by syncopal or sudden death episodes in patients with a structurally normal heart and a characteristic electrocardiogram 9 showing a pattern of right bundle branch block and ST segment elevation in right precordial leads V1 to V3. The disease is genetically determined with and autosomic dominant pattern of transmission. Until now three mutations and one polymorphism in the sodium cardiac channel gene have been identified in two families and one sporadic patient. As in many other genetically determined diseases, the disease is heterogeneous, caused by more than one gene. The syndrome has been identified in almost all countries in the world. Its incidence is difficult to evaluate, but it seems to be responsible for 4 to 10 sudden deaths per year per 10,000 inhabitants in areas like Laos or Thailand, and it represents the most frequent cause of death in young male adults in these countries. Up to 50% of all sudden deaths in patients with structurally normal heart are caused by the disease. The diagnosis can be easily made thanks to the characteristic electrocardiographic pattern. In some patients, the presence of concealed and intermittent forms might make the diagnosis more difficult. The electrocardiogram can be modulated by autonomic changes and administration of antiarrhythmic drugs. Beta-adrenergic stimulation normalizes the electrocardiogram, whereas ajmaline, flecainide or procainamide administration increase ST segment elevation. These drugs allow the unmasking of concealed or intermittent forms of the disease. Prognosis of patients with the syndrome is poor without an implantable defibrillator and antiarrhythmic drugs like amiodarone or betablockers do not protect against sudden death. The poor prognosis is similar in patients with a history of aborted sudden death or syncope and in asymptomatic patients in whom the abnormal electrocardiogram characteristic of the syndrome, was identified during a routine examination.
Brugada
J
J
Hospital Clínic, Universitat de Barcelona, España. jepbrugada@grn.es
Brugada
P
P
Brugada
R
R
D019571:Arrhythmogenic Right Ventricular Dysplasia / Q000175:diagnosis / Q000453:epidemiology / Q000209:etiology / Q000235:genetics / Q000473:pathology; D002037:Bundle-Branch Block / Q000175:diagnosis / Q000453:epidemiology / Q000209:etiology* / Q000235:genetics / Q000473:pathology; D009202:Cardiomyopathies / Q000175:diagnosis / Q000453:epidemiology / Q000209:etiology* / Q000235:genetics / Q000473:pathology; D016757:Death, Sudden, Cardiac / Q000209:etiology* / Q000473:pathology; D004562:Electrocardiography; D006439:Hemodynamics; D006801:Humans; D015994:Incidence; D011379:Prognosis; D013577:Syndrome