PAC's With RBBB Aberration-KH

Frank Yanowitz Copyright 1996

These PAC's, indicated by arrows, enter the ventricles and find the right bundle refractory. They therefore conduct with RBBB aberrancy. In most normal hearts the right bundle recovery time is longer than the left bundle's; most aberrancy, therefore, has a RBBB morphology. In some diseased hearts the left bundle may have a longer refractory period resulting in LBBB aberration. Aberrant conduction may also involve the fasicles of the left bundle.