Although much less common than in south–eastern Asia this syndrome is not rare in western countries and in North America.

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• I. CLINICAL FEATURES
  Symptoms, particularly syncope and sudden death, usually appear between the ages of 40 and 50. These symptoms occur with no warning. In one study of 163 patients in which ventricular fibrillation occurred in 22% percent, the following observations were made: 12:1 male to female ratio, 58% of Asian origin, and mean age at first abnormal heart rhythm detected was 22–65, but occurred more often in the 40–50 age group. Most of these patients had a family history of syncope, sudden death, or abnormal ECG changes.
• II. PERSPECTIVE
  The exact mechanism of the electrocardiographic changes and the development of ventricular fibrillation and sudden death remain undetermined. Electrically active cardiac cells possess sodium channels; an outward sodium current is counterbalanced by an inward sodium current. It appears that in this syndrome the inward current is attenuated and some of the electrocardiographic features can be partly explained based on changes in sodium currents. The syndrome is a disorder of sodium cardiac channel func¬tion that triggers the electrocardiographic changes and malignant arrhythmias, particularly ventricular fibrillation. Mutations in a gene responsible for the sodium chan¬nel have been identified in some families with this syn¬drome. More than three different mutations on the cardiac sodium channel gene SCN5A on chromosome 3 have been described. Mutations on other genes are being sought. Further research is required in this area and its results are of extreme importance to prevent deaths in young individuals.
• BIBLIOGRAPHY
  Antzelevitch, C., Brugada, P., Brugada, J., Brugada, R., Towbin, J. A.,