Conduction Defects

Electrocardiographic manifestation of the middle fibers/septal fascicle block: a consensus report

“…e) The permanent ECG pattern of PAF has been described as due to incomplete RBBB, 25,33 some type of WPW preexcitation, RV enlargement, lateral infarction, or possible MF/SF block. 11,26,27 In case of incomplete RBBB, a slurred or small notch in the ascending limb of the S wave is often observed. However, in other instances, a fine RS pattern is seen and in the VCG study of Piccolo et al, 23 there was no more slowness of the terminal part of the loop than before the anterior shifting of the loop.…”

Controversies about the terminology of “trifascicular” block

“…Other descriptions of trifascicular block may further complicate the understanding of the conduction system. The description of trifascicular block in 2012 Macfarlane's book on Electrocardiology is a good example 4 . Trifascicular block is described as “the term used for the possible combination of complete or incomplete block in the right bundle branch associated with conduction disturbances either in the two main divisions of the left bundle branch or one of them plus an intra‐Hisian delay.…”