[Preload].
D000818:Animals; D001794:Blood Pressure; D002302:Cardiac Output; D002306:Cardiac Volume; D003971:Diastole; D004285:Dogs; D006321:Heart / Q000502:physiology*; D006331:Heart Diseases / Q000503:physiopathology; D006439:Hemodynamics; D006801:Humans; D009200:Myocardial Contraction; D005082:Physical Exertion; D011652:Pulmonary Circulation; D011667:Pulmonary Veins / Q000502:physiology