1 - heart anatomy
TRANSCRIPT
HeartAnatomy
Heart
The heart is a hollow muscular organ that pumps blood through the blood vessels to
all the tissues.
The scientific study of the normal heart and the diseases associated with it is known as cardiology.
(Gk: cardio – heart and logos - study)
Heart
Shape Hollow cone with broad base and narrow apex
Size Closed fist (Length = 12 cm & width = 9 cm)
Mass Adult male = 300 gramAdult female = 250 gram
Origin Mesodermal
Location of heart
a. Inferior view of cross section of thoracic cavity
Right lung
Mediastinum
Sternum
Vertebra
Left lung
b. Anterior view of the heart in the thoracic cavity
Location of heart
Right lung
Diaphragm
Left lung
Heart
Pericardium
Pericardium is a double layered membrane that surrounds and protects
the heart.
Pericardium
Outer parietal pericardium
Layers of the pericardium
Serous layer
Inner visceral pericardium
Pericardial cavity
Fibrous layer
Layer Sub-layer Description Function
Outer parietal pericardium
Fibrous pericardium Made up of fibrous connective tissue
• Protects the heart• Prevents overfilling of
the heart with blood
Serous pericardium
Made up of squamous epithelial cells
• Secretes a pericardial fluid which reduces friction during relaxation & contraction of heart
Inner visceral pericardium - Made up of flattened
epithelial cells• Adheres to heart
forming its outer covering
Layers of the heart wall
Epicardium (outer)
Subepicardial fat
Myocardium (middle)
Endocardium (inner)
Layer Description Function
Epicardium Made up of single layer of flat epithelial cells called mesothelium
Imparts a smooth, slippery texture to the outermost surface of the heart
Myocardium Thickest layer made up of cardiac muscle fibres
Responsible for pumping action of the heart
Endocardium Made up of single layer of flat epithelial cells called endothelium
Provides a smooth lining for the chambers of the heart
Chambers of the heart
Right atrium
Left atrium
Right ventricle
Left ventricle
Four Chambers: Two superior
chambers (Atria)
Two inferior chambers (Ventricles)
RA
LA
Systemic Aorta
Blood vessels arising from the chambers of the heart
RVLV
Superior vena cava
Right pulmonary artery
Pulmonary trunk
Left pulmonary artery
Right pulmonary veinsLeft pulmonary veins
Inferior vena cava
Chamber Description Function
Atria• Small thin walled
• Right atrium is larger than left atrium
• Right atrium receives deoxygenated blood from all over the body through superior & inferior vena cava
• Left atrium receives oxygenated blood from the lungs through four pulmonary veins
Ventricles
• Large thick walled
• Wall of left ventricle is three times thicker than right ventricle
• Inner surface consists of muscular ridges called columnae carnae or trabeculae carnae
• Right ventricle pumps deoxygenated blood to lungs
• Left ventricle pumps oxygenated blood to all parts of the body
Septa of the heart
RA
LA
RV
LV
Interatrial septum
Interventricular septum
• A shallow depression on the right side of interatrial septum
• Represents a remnant of foramen ovale in foetus
Fossa ovalis
RA
RV
Fossa ovalis
Coronary vein
Atrioventricular (Coronary sulcus)
Sulci of the heart
Interventricular sulcus
Coronary artery
Receives deoxygenated blood from the tissues
of the heart
Supply oxygenated blood to the tissues of
the heart
Valves of the heart
Pulmonary valve
Right AV valve
Papillary muscles
Aortic valve
Chordae tendinae
Left AV valve
Valves of the heart
Right AV valve(tricuspid)
Left AV valve(bicuspid or mitral)
Aortic valve(tricuspid)
Pulmonary valve(tricuspid)
Valves of the heartType Valve Position Function
Atrioventricular valve
Right AV valve(tricuspid)
Between right atrium and right ventricle Prevent backflow of
blood into the atria when ventricles contractLeft AV valve
(bicuspid or mitral)Between left atrium and
left ventricle
Semilunar valve
Aortic valve(tricuspid)
Between left ventricle and aorta
Prevent backflow of blood into the ventricles
Pulmonary valve(tricuspid)
Between right ventricle and pulmonary trunk