I
formed behind the corresponding sternoclavicular joint
by the union of the internal jugular and subclavian veins
(Fig. 1e.1).Coulse
The superior vena cava is about 7 cm long. It begins
behind the lower border of the sternal end of the first
right costal cartilage, pierces the pericardium opposite
the second right costal cartilage, and terminates by
opening into the upper part of the right atrium behind
the third right costal cartilage (Fig.79.2).It has no
valves.Relotions
L Anterior
a. Chest wall.
b. Internal thoracic vessels.
c. Anterior margin of the right lung and pleura.
d. The vessel is covered by pericardium in its lower
half (Fig. 1e.2).
2 Posterior
a. Trachea and right vagus (posteromedial to the
upper part of the vena cava) (see Fig.16.2).
b. Root of right lung posterior to the lower part.
3 Medinl
a. Ascending aorta.
b. Brachiocephalic artery.
4 Laternl
a. Right phrenic nerve with accompanying vessels.
b. Right pleura and lung (Fig. 19.3).Tribuloiles
1 The azygosvein arches over the root of the right lung
and opens into the superior vena cava at the level of
the second costal cartilage, just before the latter enters
the pericardium.
2 Several small mediastinal and pericardial veins drain
into the vena cava.INTRODUCT!ON
Superior vena cava brings deoxygenated blood from
the head and neck, upper limbs and thorax to the heart.
Aorta and pulmonary trunk are the only two exit
channels from the heart, developing from a single
truncus arteriosus. The two are intimately related to
each other.DISSECIION
Trace superior vena cava from level of first right costal
cartilage where it is formed by union of left and right
brachiocephalic veins tillthe third costal cartilage where
it opens into right atrium.
Trace the ascending aorta from the vestibule of left
ventricle upwards between superior vena cava and
pulmonary trunk.
Arch of aorta is seen above the bifurcation of
pulmonary trunk.
Cut ligamentum aderiosum as it connects the left
pulmonary artery to the arch of aofta.
Trace the left recurrent laryngeal nerve to the medial
aspect of arch of aofta.
Lift the side of oesophagus foruvards to expose the
anterior surface of the descending aofta.
Lift the diaphragm fonrvards and expose the aofia in
the inferior part of the posterior mediastinum.SUPERIOR VENA C
Superior vena cava is a large venous channel which
collects blood from the upper half of the body and
drains it into the right atrium. It is formed by the union
of the right and left brachiocephalic or innominate veins
behind the lower border of the first right costal cartilage
close to the sternum. Each brachiocephalic vein is
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