title: Atrial electrical alternans.
mesh_terms: D000368:Aged; D004562:Electrocardiography; D006325:Heart Atria / Q000503:physiopathology*; D006329:Heart Conduction System / Q000503:physiopathology; D006333:Heart Failure / Q000175:diagnosis / Q000503:physiopathology; D006801:Humans; D008297:Male