title: Tachycardia-dependent second degree AV-block in a patient with right bundle branch block.
abstract: A 55-year old male patient, with dizzy spells during everyday activity and a complete right bundle branch block as the sole electrocardiographic abnormality, reproducibly demonstrated tachycardia-dependent Mobitz Type II- and 2:1 second degree atrioventricular block. An electrophysiologic study revealed a provocable block within the distal portion of the bundle of His without evidence of a split His potential. Because of the truly tachycardia-dependent AV-block, beta-blocker medication was initiated to prevent high sinus rates during everyday activity. This therapy abolished symptoms totally.
mesh_terms: D000404:Ajmaline / Q000627:therapeutic use; D002036:Bundle of His / Q000503:physiopathology; D002037:Bundle-Branch Block / Q000188:drug therapy / Q000503:physiopathology*; D002304:Cardiac Pacing, Artificial; D004562:Electrocardiography; D006327:Heart Block / Q000188:drug therapy / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011690:Purkinje Fibers / Q000503:physiopathology; D013610:Tachycardia / Q000503:physiopathology*
chemical_list: D000404:Ajmaline