Mechanisms of contraction of the normal and failing heart.
D000818:Animals; D006321:Heart / Q000502:physiology* / Q000503:physiopathology*; D006329:Heart Conduction System / Q000502:physiology*; D006333:Heart Failure / Q000503:physiopathology*; D006339:Heart Rate; D006801:Humans; D009119:Muscle Contraction; D009206:Myocardium / Q000378:metabolism*; D005082:Physical Exertion / Q000502:physiology