Automatic assessment of right ventricular repolarisation dispersion during diagnostic ajmaline test for suspected Brugada syndrome

We used principal components analysis (PCA) to quantify right ventricular (RV) repolarisation dispersion during diagnostic ajmaline test for suspected Brugada syndrome (BS). 10-second 15-lead electrocardiograms (ECG) (500 Hz, 12 standard leads + V1 to V3 from 3^rd intercostal space, V1h to V3h) were acquired in 61 patients (pts) with suspected BS (38 men, age 39±17 years) during ajmaline administration. PCA (ratio 2^nd/1^st eigenvalue) was performed on the J-T_end interval using a) leads V1 to V3 (PCA_stand), b) V1h to V3h (PCA_high) and c) V1 to V3 + V1h to V3h (PCA_total). Pts with positive tests (n=20) had significantly higher PCA_high and PCA_total, on pre-test ECGs than those with negative tests. The maximum drug-induced increase of PCA was significantly greater in pts with positive than in those with negative tests (e.g. PCA_high 6406±12622% vs 192±350%, p=0.004). Assessment of RV repolarisation dispersion using PCA can help the diagnosis of BS.