title: [Heart rhythm].
mesh_terms: D000200:Action Potentials; D000293:Adolescent; D000328:Adult; D000368:Aged; D000375:Aging; D000663:Amphibians; D000818:Animals; D001341:Autonomic Nervous System / Q000502:physiology; D001831:Body Temperature; D001835:Body Weight; D002648:Child; D002675:Child, Preschool; D006339:Heart Rate; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008322:Mammals; D008564:Membrane Potentials; D008875:Middle Aged; D011188:Potassium / Q000502:physiology; D012104:Reptiles; D012964:Sodium / Q000502:physiology; D013045:Species Specificity
chemical_list: D012964:Sodium; D011188:Potassium