The contractile function of the myocardium in two types of cardiac adaptation to a chronic load.

Adaptation, Physiological Altitude Animals Aortic Coarctation/physiopathology Atmosphere Exposure Chambers Biomechanical Phenomena Cardiomegaly/physiopathology Disease Models, Animal Electric Stimulation Heart/physiopathology Hypoxia/physiopathology Male Muscle Tonus Muscles/physiopathology Organ Size Papillary Muscles/physiopathology Rats