Assessment of repolarization based on body surface measurements

Activation recovery interval (ARI) has been recently introduced for assessment of repolarization on the cardiac surface. Due to the inhomogeneous conducting effect of the torso we apply statistical tools (first and second moments) for interpreting ARI on the body surface. Variance analysis (Tukey´s and Scheffe´s test) was accomplished using data of 418 patients. The pathological groups were found to be significantly different from normal. The pair-wise classifications of normal with arrhythmia, CAD and infarcts, yielded 93.2%, 79.2% and 72.3% true negative rate, respectively, with sensitivity of 94.3% and specificity of 80.9 %. Using the variance of ARI, we achieved the best result in separation of normal and arrhythmia groups, supporting the hypothesis that enhanced ARI variance is a risk factor for VA vulnerability.