title: A study of reciprocal rhythm with concealed conduction.
mesh_terms: D000368:Aged; D004562:Electrocardiography; D005260:Female; D006329:Heart Conduction System / Q000503:physiopathology*; D006352:Heart Ventricles / Q000503:physiopathology; D006801:Humans; D013610:Tachycardia / Q000175:diagnosis* / Q000503:physiopathology