title: Two-to-one A-V block with four-to-three A-V nodal wenckebach, a form of spontaneous multilevel block.
abstract: Electrophysiologic studies in one patient with spontaneous 2:1 atrioventricular block and variable PR intervals revealed two sites of conduction block. Typical 4:3 A-V nodal Wenckebach was present in addition to Mobitz type II infra-His block. The HV of conducted complexes was 120 msec and the shortest recorded AH interval was 250 msec. When 2:1 A-V block with fixed PR interval was present, only 2:1 Mobitz type II infra His-block was present. The mechanism of this example of spontaneous multilevel A-V block is discussed and compared to other previously reported cases.
mesh_terms: D000368:Aged; D004562:Electrocardiography; D004594:Electrophysiology; D006321:Heart / Q000503:physiopathology*; D006327:Heart Block / Q000503:physiopathology*; D006329:Heart Conduction System / Q000503:physiopathology; D006801:Humans; D008297:Male