title: Sinus escape-capture bigeminy alternating with sinus extrasystolic bigeminy: dual atrial response and apparent sinus escape.
abstract: We report here five cases of sinus bigeminy in which comparatively long PP intervals alternated with comparatively short PP intervals, suggesting 'sinus escape-capture bigeminy' or 'sinus extrasystolic bigeminy'. In three of the cases, these two forms of sinus bigeminy were found in the same patient. This is the first study on 'sinus escape-capture bigeminy' alternating with 'sinus extrasystolic bigeminy'. The electrocardiographic findings in these cases suggest the possibility that 'sinus escape' in the sinoatrial junction is not true escape. Attempts are made to explain that apparent sinoatrial junctional escape occurs as a result of markedly slow conduction through the slow sinoatrial pathway, using the concepts of 'dual sinoatrial pathways' and 'double atrial response'.
authors.affiliation: Hokkaido University, Sapporo, Japan bKatoh Cardiovascular Clinic, Ohtsu, Japan. kinoshita-s@mri.biglobe.ne.jp
authors.forename: Shinji
authors.initials: S
authors.lastname: Kinoshita
authors.forename: Takakazu
authors.initials: T
authors.lastname: Katoh
mesh_terms: D000200:Action Potentials; D000328:Adult; D000368:Aged; D001146:Arrhythmia, Sinus / Q000503:physiopathology; D001145:Arrhythmias, Cardiac / Q000503:physiopathology*; D018880:Atrial Premature Complexes / Q000503:physiopathology; D001283:Atrioventricular Node / Q000503:physiopathology*; D004562:Electrocardiography; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012848:Sinoatrial Block / Q000503:physiopathology; D013997:Time Factors