Abstract 2147: Utility of Multichannel Holter ECG Recording at the Third Intercostal Space to Diagnose A Type 1 Brugada ECG; Comparison with Repeated 12-Lead ECGs
The detection of a type 1 Brugada ECG is essential for diagnosis and risk stratification in Brugada syndrome. In this study, we evaluated the detection rate of a type 1 ECG on the multichannel Holter ECG, compared with the 12-lead ECGs recorded repeatedly. We enrolled consecutive 60 patients who had eventually exhibited a diagnostic type 1 ECG in the presence or absence of Na+ channel blockers at either standard or the third intercostal position. All patients underwent 12-lead ECGs recorded at both standard and the third intercostal position at least 5 times between 0 p.m and 2 p.m (4L-ECGs, 3L-ECGs, respectively). The 24-hour Holter ECG was performed in all patients, using a 12-lead Holter recording system. The precordial electrodes were attached at the standard position of V1, V2, V5, V6 and the third intercostal space of V1 and V2 (V1IC3, V2IC3, respectively). The leads V1 and V2, and V1IC3 and V2IC3 on the Holter ECG were expressed as 4L-Holter and 3L-Holter, respectively. The diagnostic type 1 ECG on the Holter ECG was defined as a presence of a coved-type ST-segment elevation >0.2mV over continuous 60 seconds at least one lead. We evaluated the detection rate of the type 1 ECG in 4L-ECGs, 3L-ECGs, 4L-Holter and 3L-Holter, and compared them among the 4 different recording methods. Among 60 patients, the patients showing the type 1 ECG on 4L-ECGs, 3L-ECGs, 4L-Holter and 3L-Holter were 15 (25%), 26 (43.3%), 23 (38.3%) and 33 patients (55%), respectively. The detection rate in 3L-ECGs and 3L-Holter was significantly larger than that in 4L-ECGs (p=0.03, p<0.001, respectively). Additionally, in 8 (23.5%) out of 34 patients with drug-induced type 1 ECG at standard and/or the third intercostal position, a spontaneous type 1 ECG was detected in 3L-Holter. Although the detection rate of a type 1 ECG in 3L-Holter was not significantly different with that in 3L-ECGs, the 3L-Holter was the most sensitive to detect a type 1 ECG among the 4 recording methods. In patients with Brugada type ECG, the Holter ECG recorded in the right precordial leads at the third intercostal space is more sensitive method to detect a diagnostic type 1 ECG than repeated 12-lead ECGs or the Holter ECG at standard position.