title: [Left bundle of His branch block in stages 3 and 4 with conduction in the right branch only in a super-normal period].
abstract: The authors report a case of chronic second degree atrio-ventricular block with permanent right bundle branch block. Intracavitary electrophysiological recordings allowed them to delimit the refractory period of the left branch, which was affected by a block during phase 3 but also during phase 4. They showed that there was possible conduction by the right branch during the extremely fine time limits of a supernormal period; using an atrial stimulation rate of 150/mn, it is therefore possible to obtain 1/1 conduction in the presence of a left bundle branch block.
mesh_terms: D000368:Aged; D002036:Bundle of His / Q000503:physiopathology*; D002037:Bundle-Branch Block / Q000503:physiopathology*; D002908:Chronic Disease; D005260:Female; D006327:Heart Block / Q000503:physiopathology; D006329:Heart Conduction System / Q000503:physiopathology*; D006801:Humans; D008297:Male
vernacular_title: Bloc en phase 3 et en phase 4 de la branche gauche du faisceau de His et conduction uniquement en phase super-normale dans la branche droite.