Recent advances in the diagnosis of fascicular blocks

This presentation has shown that indeed some electrocardiographic patterns may reflect delayed, or absent, arrival of excitation at the corresponding portions of the left ventricular muscle through the different fascicles of the left branch. Although various working criteria have been proposed due to the requirements imposed by the need to interpret clinical electrocardiograms, it is possible to conclude that the sensitivity and specificity of these criteria still require independent confirmation. The newer techniques of cathether mapping and phase imaging appear promising in this respect.