title: The AV nodal Wenckebach phenomenon as a positive feedback mechanism.
mesh_terms: D000368:Aged; D004562:Electrocardiography; D005246:Feedback; D005260:Female; D006321:Heart / Q000187:drug effects; D006327:Heart Block / Q000175:diagnosis / Q000503:physiopathology; D006329:Heart Conduction System / Q000502:physiology* / Q000503:physiopathology; D006801:Humans; D006973:Hypertension / Q000503:physiopathology; D008297:Male; D008875:Middle Aged