Brugada syndrome without mutation of the cardiac sodium channel gene in a Taiwanese patient.

We describe a 45-year-old Taiwanese man with specific features of Brugada syndrome but no clinical features of structural heart disease. He was successfully treated with an implantable cardioverter-defibrillator. His electrocardiogram (ECG) patterns changed intermittently. Alpha-adrenoceptor stimulation and beta-adrenoceptor blockade augmented the characteristic ST-segment elevation, whereas alpha-adrenoceptor blockade and beta-adrenoceptor stimulation mitigated the ST-segment elevation. Intravenous procainamide administration did not aggravate ST-segment elevation when ECG had shown coved ST elevation in the right precordial leads. Molecular study did not reveal the same mutations in the cardiac sodium channel gene (SCN5A) as previously reported in Brugada syndrome. This case demonstrates the genetic heterogeneity of SCN5A in Brugada syndrome.