The heart is a hollow muscular organ that pumps blood through the blood vessels. It is located in the mediastinum of the thoracic cavity. The heart is surrounded and protected by the pericardium, which has inner and outer layers. Within the heart are four chambers - two upper atria that receive blood and two lower ventricles that pump blood out. Valves between the chambers prevent backflow of blood. The heart is supplied with oxygenated blood by the coronary arteries.

1. Heart
Anatomy

2. 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)

3. Heart
Shape
Hollow cone with broad base and
narrow apex
Size
Closed fist
(Length = 12 cm & width = 9 cm)
Mass
Adult male = 300 gram
Adult female = 250 gram
Origin Mesodermal

4. Location of heart
a. Inferior view of cross section of thoracic cavity
Right lung
Mediastinum
Sternum
Vertebra
Left lung

5. b. Anterior view of the heart in the thoracic cavity
Location of heart
Right lung
Diaphragm
Left lung
Heart

6. Pericardium
Pericardium is a double layered
membrane that surrounds and protects
the heart.

7. Pericardium
Outer parietal
pericardium
Layers of the pericardium
Serous layer
Inner visceral
pericardium
Pericardial cavity
Fibrous layer

8. 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

9. Layers of the heart wall
Epicardium (outer)
Subepicardial fat
Myocardium (middle)
Endocardium (inner)

10. 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

11. Chambers of the heart
Right
atrium
Left
atrium
Right
ventricle
Left
ventricle
Four Chambers:
 Two superior
chambers
(Atria)
 Two inferior
chambers
(Ventricles)

12. RA
LA
Systemic Aorta
Blood vessels arising from the chambers of the heart
RV
LV
Superior vena cava
Right pulmonary artery
Pulmonary trunk
Left pulmonary artery
Right pulmonary veins
Left pulmonary veins
Inferior vena cava

13. 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

14. Septa of the heart
RA
LA
RV
LV
Interatrial
septum
Interventricular
septum

15. • A shallow depression
on the right side of
interatrial septum
• Represents a remnant
of foramen ovale in
foetus
Fossa ovalis
RA
RV
Fossa ovalis

16. 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

17. Valves of the heart
Pulmonary valve
Right AV valve
Papillary muscles
Aortic valve
Chordae tendinae
Left AV valve

18. Valves of the heart
Right AV valve
(tricuspid)
Left AV valve
(bicuspid or mitral)
Aortic valve
(tricuspid)
Pulmonary valve
(tricuspid)

19. Valves of the heart
Type 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