ANATOMY OV THE HEART 



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with the smaller end below and slightly to the left of the 

 breastbone. It is this position of the point that malves the 



Fig. 65 — External view of the heart; Z/, Z, lungs; RA, right auricle; LA, left 

 auricle; RV, right ventricle; LV, left ventricle; JVC, inferior vena cava; 

 *S VC, superior vena cava ; Ao, aorta ; PA, pulmonary artery ; Tr, trachea. 



beating more distinctly felt on the left side of the body, 

 but the bulk of the organ is in the middle of the cavity. 

 The heart is surrounded by a sac called the pericardium. 



