Heart: Location, External and internal anatomy (mediastinum, pericardium, epicardium,
myocardium, endocardium), Chambers, valves (atrioventricular and semilunar),
Histology of muscle tissue, Heart sounds
-Mediastinum= Location of the heart, between your lungs in the middle of chest
-Pericardium= Around the heart (keeps stable)
2 layers of the pericardium; Serous and Visceral
Serous= Outer layer & Visceral= at organ and inner layer of surrounding
pericardium
-Epicardium= outside layer
-Myocardium= middle layer; main surface of the heart
-Endocardium= inner layer
-2 upper atriums and 2 lower ventricles (left side is thicker then the right side of heart
because its stronger from pumping blood to the rest of the body
-LEFT atrium= Chambers that receive oxygenated blood from pulmonary
veins and pumps into systemic circulation!
-LEFT ventricle= Pumps oxygenated blood to the body= oxygen RICH!
-RIGHT atrium= Receives deoxygenated blood from the blood= oxygen
POOR!
-RIGHT ventricle= Pumps deoxygenated blood to the lungs = oxygen
POOR!
-Valves prevent the bad flow, one set of valves is open the other set is closed, valves
open in response to pressure changes from the heart contracting and relaxing !
-Atrioventricular Valve= Prevents back-flow R. And L. Into atriums
-Semilunar Valve= Prevents back-flow R. and L. Into ventricles
-Histology of Cardiac Muscle Tissue= Made of Dense connective tissue with elastic
fibers present in the cardiac/ fibrous skeleton
-Heart Sounds= Valve closing, One opens the other closes, mechanical events affect
the phases of the heart, and “iso” means same volume on either side of heart
4 normal heart sounds;
s1= “lub” closing of the AV valves, s2= “dub” closing of semilunar valves, s3= linked with
the flow of blood into the ventricles( most critical), and s4 linked with partial contraction
