Abstract 2694: Atrial Electrical Activity is Abnormal in Brugada Syndrome
(Background) Brugada syndrome is commonly considered a disease of the ventricle. However, suggesting an abnormal atrial electrical activity, paroxysmal atrial fibrillation(PAF) occurs in Brugada syndrome as well. Accordingly, we examined by Signal-averaged ECG(SAECG) whether there is an abnormal atrial electricity is present in Brugada syndrome.
(Methods and Results) SAECG during normal sinus rhythm was performed in 63 normal volunteers (control), 21 patients with a PAF, and 21 with Brugada syndrome (Brugada). All patients with PAF had no other cardiac disease. All patients with Brugada syndrome showed the typical electrocardiographic “Brugada sign”. 11 patients of Brugada syndrome had VF or induced VF by electrophysiological study. 6 patients of Brugada syndrome had history of PAF. In the QRS wave SAECG, the filtered QRS wave duration (fQRSd) was significantly prolonged in patients with Brugada (134.3 ± 14.9ms) compared to control (116.8 ± 9.3ms, p<0.0001) and PAF (120.0 ± 10.5ms, p<0.0001). There was no significant difference in fQRSd between control and PAF. RMS40 was significantly lower in Brugada (14.7 ± 9.3μV) compared to control (26.8 ± 13.9μV, p<0.01) and PAF (26.6±18.7μV, p<0.01). There was no significant difference in RMS40 between control and PAF. In the P wave SAECG, the filtered P wave duration (fPd) was significantly prolonged in PAF (134.3 ± 17.9ms) compared to control (118.5 ± 11.2ms, p<0.0001) and Brugada (125.3 ± 14.9ms, p<0.05). fPd was prolonged in Brugada compared to control (p<0.05). P-RMS20 was significantly lower in PAF compared to control (p<0.05). However there was no significant difference in P-RMS20 between control (2.70 ± 1.16μV) and Brugada (2.64 ± 1.00μV), and between Brugada and PAF (2.11 ± 1.11μV).
(Conclusion) An electrical abnormality of the myocardium may exist not only in the ventricle but also in the atrium.