title: Myocardial K+ loss and contraction frequency.
mesh_terms: D000251:Adenosine Triphosphatases / Q000378:metabolism; D006339:Heart Rate; D006801:Humans; D009119:Muscle Contraction; D009206:Myocardium / Q000378:metabolism*; D011188:Potassium / Q000378:metabolism*; D012964:Sodium / Q000378:metabolism
chemical_list: D012964:Sodium; D000251:Adenosine Triphosphatases; D011188:Potassium