A simplified method of recognizing anterior divisional blocks (hemiblocks): a hexaxial system approach.
A simplified method of diagnosing anterior divisional blocks (hemiblocks) at a glance is made possible by using a knowledge of the lead line directions on a hexaxial system. The term 'divisional block' is preferred to 'hemiblock' because a block of one of the three divisions of the left bundle cannot be a hemiblock. The diagnosis of an anterior divisional block can be simplified by utilization of the concept that it is mainly a terminal conduction abnormality in the frontal plane with a direction between -60 degree and -90 degree. Using a hexaxial system the diagnosis can be quickly made regardless of axis by simply noting the presence of a terminal negativity (S wave) in aVF, terminal positivity in aVR (R or R'), and no S in lead 1.
Constant
J
J
Department of Medicine, State University of New York at Buffalo, USA.
D002036:Bundle of His / Q000503:physiopathology; D002037:Bundle-Branch Block / Q000175:diagnosis* / Q000503:physiopathology; D004562:Electrocardiography / Q000379:methods*; D004566:Electrodes; D006801:Humans; D014672:Vectorcardiography / Q000379:methods