Utility of high and standard right precordial leads during ajmaline testing for the diagnosis of Brugada syndrome

Aims The authors sought to assess the value of the high right precordial leads (RPL) to detect the Type I Brugada ECG pattern in patients suspected of carrying Brugada syndrome (BrS). Methods Ajmaline testing using 15-lead ECGs was performed in 183 patients suspected of carrying BrS. Standard 12-lead ECG with V1-V3 recorded from the fourth intercostal space and an additional three leads placed over V1-V3 recorded from the third intercostal space were analysed. ECGs were analysed for a Type I ECG pattern in either the standard or high RPLs. Results Of the 183 tests, 31 (17%) were positive, and 152 were negative. In all positive studies, at least one high RPL became positive. In 13/31 (42%) cases, the Type I ECG pattern could be observed only in the high RPLs. Standard or high V3 were never positive before standard or high V1-V2. In seven patients, a Type I pattern was seen in one standard and one high RPL (vertical relationship). Conclusions The high RPLs are more sensitive than the conventional 12-lead ECG alone and initial observations suggest that they remain specific for BrS, while standard and high lead V3 offer redundant data. A vertical relationship of type 1 patterns may have a similar diagnostic value to that of a horizontal pair.