Anatomy of
the Heart

Shape &
Position of the
heart

Shape
The heart has an apex
and a base because the
heart is pyramidal in
shape.
The base of the heart in
the normal anatomical
position should be
directed posteriorly and
apex should be directed
forwards, downwards
and to the left.

Position of the
heart
The normal heart occupies less
than 50% of the trans-thoracic
diameter in the frontal plane, as
seen on the Chest x-ray.
The heart is present in the middle
mediastinum; The Mediastinum
extends from the posterior aspect
of the sternum to the anterior
surface vertebral column.
The human
heart is in the
middle of
the thorax, with
its apex pointing
to the left.

Surface Anatomy

Layers of the
heart

Layers of the
heart wall,
including
visceral and
parietal
pericardium.

Surfaces of the
heart

Anterior S Posterior S Diaphragmatic S

Surfaces of the heart
1.Sternocostal (anterior)
surface
This surface is formed by the 4 chambers
Of the heart but the greater part of this surface
is formed by the right ventricle and the right
atrium.
 There are two grooves in the
sternocostal Surface :
A. Atrio-Ventricular groove:
The coronary arteries lies in this groove.
B. Anterior interventricular groove:
It contains the anterior interventricular
artery and the great cardiac vein.
2. Posterior surface (base) of
the heart
It is formed by the back of both
the left
and the right atria.
 The 4 pulmonary veins
entering the left Atrium and
superior and inferior venae
cavae entering the right
atrium.
3. The diaphragmatic surface
This surface rests on the
diaphragm.
It is formed by both ventricles (
mainly the left ).
 The posterior interventricular
groove
which contains the posterior
interventricular branch of the
right coronary artery
and the middle cardiac vein.

Blood supply
of the heart

Blood Supply of the Heart
(coronary circulation)
1.The Right coronary artery
 Arises from the anterior aortic sinus of the
ascending aorta.
 It gives : - marginal branch
- posterior interventricular artery
 It ends by anustomosing with the
circumflex branch of the left coronary
artery.
2. The left coronary artery
 Arise from the left posterior aortic sinus of
the ascending aorta.
 It is short and ends by dividing into two
branches:
- Anterior interventricular artery
- Circumflex branch

Coronary circulation

Blood Supply of the Heart
(Venous Drainage)
1) Coronary Sinus:
It receives veins from the
heart and then opens in
the right atrium
The veins that drains in
the coronary sinus are:
a. Great cardiac vein
b. Middle cardiac vein
c. Small cardiac vein
d. Oblique cardiac vein
e. Posterior vein
2) Anterior cardiac veins:
One or 2 veins open directly
into right atrium which drain
the anterior wall of the right
ventricle
3) Vena cordis minimae:
 They are small veins that begin
in the myocardium of any
chamber and opens into this
chamber

Cardiac veins

Chambers of
the heart

The heart has four
chambers:
two atria and two ventricles.
The right atrium receives
oxygen-poor blood from the
body and pumps it to the right
ventricle.
The right ventricle pumps the
oxygen-poor blood to the
lungs.
The left atrium receives
oxygen-rich blood from the
lungs and pumps it to the left
ventricle.
The left ventricle pumps the
oxygen-rich blood to the body.

Valves of the
heart

Valves of the heart
1) Tricuspid valve:
Found between the right atrium and the right ventricle
2) Mitral Valve ( Bicuspid valve):
It is on the left side of the heart and allows the blood to flow from the left atrium into
the left ventricle.
3) Pulmonary valve:
 Lies between the right ventricle and the pulmonary artery, and has three cusps
4) Aortic Valve:
 Which has three cusps, lies between the left ventricle and the aorta

Blood flow through the valves
3D echocardiogram showing the mitral valve (right),
tricuspid and mitral valves (top left) and aortic valve (top
right).
The closure of the heart valves causes the heart sounds.

Pulmonary-
systemic
circulation

Pulmonary circulation

Systemic circulation

Conduction
system of the
heart

Conducting system of
the heart

The Conducting System is formed of:
SA(sino-atrial) node “ pacemaker potential “ which is responsible
for cardiac automaticity
AV (atrio- ventricular) node
AV(atrio- ventricular)bundle ( HIS )
-Right branch
-Left branch

Auscultation of
the heart