title: Observations during clinical 2:1 and 3:1 A-V block below the A-V node. Evidence of partial penetration of atrial impulses into the His bundle.
mesh_terms: D002037:Bundle-Branch Block / Q000175:diagnosis; D004562:Electrocardiography; D006327:Heart Block / Q000175:diagnosis* / Q000628:therapy; D006329:Heart Conduction System / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D010138:Pacemaker, Artificial