Be the first to comment Anatomy And Physiology of Human Heart 1. ANATOMY OF THE HEART By: Dr Mohammed Faez 2. The Heart The heart is a chambered muscular organ that pumps blood received from the veins into the arteries, thereby maintaining the flow of blood through the entire circulatory system. 3. The Heart • The heart is surrounded by membrane called Pericardium. 4. The Pericardium • The pericardium is a fibroserous sac that encloses the heart and the roots of the great vessels. • The pericardium lies within the middle mediastinum. 5. The Pericardium 6. The Pericardium • Its function is to restrict excessive movements of the heart as a whole and to serve as a lubricated container in which the different parts of the heart can contract.

1. ANATOMY OF THE HEART
By:
Dr Mohammed Faez

2. The Heart
The heart is a chambered
muscular organ that
pumps blood received
from the veins into the
arteries, thereby
maintaining the flow of
blood through the
entire circulatory
system.

3. The Heart
• The heart is surrounded
by membrane called
Pericardium.

4. The Pericardium
• The pericardium is a
fibroserous sac that
encloses the heart and
the roots of the great
vessels.
• The pericardium lies
within the middle
mediastinum.

5. The Pericardium

6. The Pericardium
• Its function is to restrict
excessive movements of
the heart as a whole
and to serve as a
lubricated container in
which the different
parts of the heart can
contract.

7. The Pericardium
• Pericardium – a double-
walled sac around the
heart composed of:
1. A superficial fibrous
pericardium
2. A deep two-layer serous
pericardium
a. The parietal layer lines
the internal surface of
the fibrous pericardium
b. The visceral layer or
epicardium lines the
surface of the heart
• They are separated by
the fluid-filled
pericardial cavity

8. The Pericardium

9. The Pericardium

10. The Pericardium

11. The Pericardium
Blood Supply
• The pericardium blood
supply is from the
pericardiacophrenic
branches of the internal
thoracic arteries.
Nerve Supply
• The pericardium nerve
supply the fibrous
pericardium and the
parietal layer of serous
pericardium are supplied by
the phrenic nerve.

12. Heart Wall
• Epicardium – visceral layer of the serous
pericardium
• Myocardium – cardiac muscle layer forming
the bulk of the heart
• Fibrous skeleton of the heart – crisscrossing,
interlacing layer of connective tissue
• Endocardium – endothelial layer of the inner
myocardial surface

13. Heart Wall
• Endocardium
– deepest layer of the
heart
– smooth lining to reduce
friction of bloodflow
• Myocardium
– middle layer of the heart
– location of muscle fibers
responsible for pumping
• Pericardium
– outer protective layer
– composed of :
– visceral pericardium
– paricardial cavity
– parietal pericardium

14. Heart Wall

15. Heart Wall

16. The Heart
• The heart is a hollow
muscular organ that is
somewhat pyramid
shaped and lies within
the pericardium in the
mediastinum .
• It is connected at its
base to the great blood
vessels but otherwise
lies free within the
pericardium.

17. The Heart

18. The Heart
The heart surfaces:
• The anterior (sternocostal) surface
comprises the: right
atrium, atrioventricular
groove, right ventricle, a small
strip of left ventricle and the
auricle of the left atrium.
• The inferior (diaphragmatic)
surface comprises the: right
atrium, atrioventricular groove
and both ventricles separated by
the interventricular groove.
• The posterior surface (base)
comprises the left atrium
receiving the four pulmonary
veins.

19. The Heart

20. The Heart Chambers
• Four chambers
– Two atria (Right and
Left)
– Two ventricles (Right and
Left)

21. The Heart Chambers
• Atria
– Features
 small, thin-walled
chambers
– Functions
 receiving chambers
for blood returning
to the heart from the
circulation
 push the blood into
the adjacent
ventricles.

22. The Heart Chambers
• Atria
– Receive blood
from
 Right side
 Superior and
Inferior Vena
Cava
 Coronary Sinus
(draining the
myocardium)
 Left side
 Pulmonary Veins

23. The Heart Chambers
• Ventricles
– Features
 make up most of
the mass of the
heart
 the walls of the
left ventricle are
3X thicker than
those of the right

24. The Heart Chambers
• Ventricles
– Functions
discharging
chambers of the
heart
propel blood to
Pulmonary Trunk
(right
ventricle), Aorta
(left ventricle)

25. The Right Atrium
• Receives deoxygenated
blood from the inferior
vena cava below and from
the superior vena cava
above.
• Receives the coronary
sinus in its lower part.
• The upper end of the
atrium projects to the left
of the superior vena cava
as the right auricle.

26. The Right Atrium
• The sulcus terminalis is a
vertical groove on the
outer surface of the
atrium. This groove
corresponds internally to
the crista terminalis .
• Above the coronary sinus
the interatrial septum
forms the posterior wall.
The depression in the
septum the fossa ovalis
are presents the site of
the foramen ovale.

28. RA

29. The Right Ventricle
• Receives blood from the
right atrium through
the tricuspid valve .
• The edges of the valve
cusps are attached to
chordae tendineae
which are, in turn,
attached below to
papillary muscles.

30. The Right Ventricle
• The wall of the right
ventricle is thicker than
that of the atria but not
as thick as that of the left
ventricle.
• The wall contains a mass
of muscular bundles
known as trabeculae
carneae.
• The infundibulum is the
smooth walled outflow
tract of the right
ventricle.

31. The Right Ventricle
• The pulmonary valve is
situated at the top of the
infundibulum.
• It is composed of three
semilunar cusps.
• Blood flows through the
valve and into the
pulmonary arteries via
the pulmonary trunk to
be oxygenated in the
lungs.

33. RV

34. The Left Atrium
• Receives oxygenated
blood from four
pulmonary veins which
drain posteriorly.
• The cavity is smooth
walled except for the
atrial appendage.
• On the septal surface a
depression marks the
fossa ovalis.

35. The Left Atrium
• The mitral (bicuspid)
valve guards the
passage of blood from
the left atrium to the
left ventricle.

36. LA

37. The Left Ventricle
• The wall of the left ventricle
is thicker than the right
ventricle but the structure is
similar.
• The thick wall is necessary
to pump oxygenated blood
at high pressure through
the systemic circulation.
• Trabeculae carneae project
from the wall with papillary
muscles attached to the
mitral valve cusp edges by
way of chordae tendineae.

38. The Left Ventricle
• The vestibule is a
smooth walled part of
the left ventricle which
is located below the
aortic valve .

40. LV

41. The Heart Valves
• Heart valves ensure
unidirectional blood flow
through the heart
– Composed of an endocardium
with a connective tissue core.
• Two major types
– Atrioventricular valves
– Semilunar valves

43. Atrioventricular (AV) Valves
• Atrioventricular (AV) valves lie
between the atria and the
ventricles
– R-AV valve = tricuspid valve
– L-AV valve = bicuspid or
mitral valve
• AV valves prevent backflow of
blood into the atria when
ventricles contract
• Chordae tendineae anchor AV
valves to papillary muscles of
ventricle wall
– Prevent prolapse of valve
back into atrium

44. Atrioventricular Valve

45. Semilunar Heart Valves
• Semilunar valves prevent
backflow of blood into the
ventricles
• Have no chordae tendinae
attachments
• Aortic semilunar valve lies
between the left ventricle and
the aorta
• Pulmonary semilunar valve lies
between the right ventricle and
pulmonary trunk
• Heart sounds (“lub-dup”) due to
valves closing
– “Lub” - closing of atrioventricular
valves
– “Dub”- closing of semilunar valves

46. Semilunar Valve

47. The Heart Valves
• Right AV (Tricuspid)
– separates the right
atrium from the right
ventricle. Prevents
backflow into atrium.
• Left AV (Bicuspid)
– separates the left atrium
from the left ventricle.
Prevents backflow into
atrium.
• Pulmonary valve
– separates the right
ventricle from the
pulmonary arteries.
Prevents backflow after
ventricular contraction.
• Aortic valve
– separates the left
ventricle from the aorta.
Prevents backflow after
ventricular contraction .
Atrioventricular valves Semilunar valves

48. The Heart Valves
Pulmonary
semilunar valve
Aortic
semilunar valve
Left AV
(bicuspid)
valve
Right AV
(tricuspid)
valve
Chordai
tendineae
Papillary
muscle

49. The Heart Valves

50. Arterial Supply of the Heart
• The arterial supply of
the heart is provided by
the right and left
coronary arteries, which
arise from the
ascending aorta
immediately above the
aortic valve.

51. Coronary Arteries
The origins of the coronary
arteries are as follows:
• The left coronary artery
arises from the aortic
sinus immediately above
the left posterior cusp of
the aortic valve .
• The right coronary artery
arises from the aortic
sinus immediately above
the anterior cusp of the
aortic valve.

52. Right coronary artery
Branches
– Right marginal arteries
(acute marginal artery)
– Posterior interventricular
artery. (in post. IV
sulcus)
– Sinoatrial nodal artery.
– Atrioventricular nodal
artery.

53. Left coronary artery
Branches
– Left anterior descending
(LAD) or anterior
interventricular artery.
(lies in anterior IV sulcus)
• Septal branches.
• Diagonal branches
– Left marginal artery.
(Obtuse marginal artery)
– Left circumflex artery.

54. Coronary Arteries

56. Venous Drainage of the Heart
• Most blood from the
heart wall drains into the
right atrium through the
coronary sinus ,which lies
in the posterior part of
the atrioventricular
groove .
• It is a continuation of the
great cardiac vein.
• It opens into the right
atrium to the left of the
inferior vena cava

57. Venous Drainage of the Heart

58. Nerve Supply of the Heart
• The heart is innervated by sympathetic and
parasympathetic fibers of the autonomic
nervous system via the cardiac plexuses
situated below the arch of the aorta.
• The sympathetic supply arises from the
cervical and upper thoracic portions of the
sympathetic trunks, and the parasympathetic
supply comes from the vagus nerves.

59. THANK YOU

63. External Heart: Anterior View

64. External Heart: Posterior View

65. Gross Anatomy of Heart: Frontal
Section