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PERICARDIUM
Pericardium is an isolated sack with heart and large blood
vessels in it. It consists of two layers: superficial fibrous
pericardium (pericardium fibrosum) and inner serous
pericardium (pericardium serosum). The pericardium fibrosum
passes into vascular layer. The pericardium serosum is divided
into two layers: visceral pericardium (lamina visceralis) which
is the part of epicardium and covers myocardium, and parietal
pericardium (lamina parietalis) which grows together with
internal surface of pericardium fibrosum and covers it from
inside.
Cavitas pericardiaca is formed
between lamina visceralis
and lamina parietalis which contains a small amount of serous
fluid.
In tuberculosis, rheumatism or injury the amount of fluid
(pericardial effusion) in pericardial cavity can increase.
Herewith diastole is getting worse, the heart beat is disturbed
what results in cardiac tamponade.
The pericardium looks like ill-formed, flattened cone, the
basis of which is located on diaphragm, and its top – on
ascending part of aorta.
Pericardium has five walls: anterior (sternocostal), two
lateral (mediastinal), posterior and diaphragmal.
Sternocostal part of pericardium
is directed to the front,
adheres to corpus sterni and to the 4th and 5th intercostal
spaces. In lateral segments and sometimes from above, the
frontal pericardial wall is covered by mediastinal edges of
parietal (right and left) pleuras. Free part of pericardium
complies with left ribs ends from the 5th to the 7th rib
cartilages, left inferior 1/3 of corpus sterni and upper 1/3 of
ensisternum. The pericardium can be exposed here without
danger of possible pleura damage. It is called “security
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triangle” of Wojnicz – Sianożęcki.
The lig. sternopericardiaca
go from the frontal part of
pericardium to sternum, and are attached to sternum at the
level of the 2nd rib.
Lateral parts of pericardium are covered by mediastinal
pleuras, in adipose tissue of which n. phrenicus and vasa
pericardiacophrenicae are located. The inferior wall of
pericardium is located on diaphragm and is fixed with
ligaments to it. V. cava inferior penetrates into pericardial
cavity through the right segment of inferior wall.
Dorsal wall of pericardium adheres
to the inferior part of
trachea and organs of mediastinum posterius – esophagus,
v. azygos, ductus thoracicus, thoracic part of aorta, n. vagus
sinistra, and lymph nodes of mediastinum posterius. The aa. and
vv. pulmonales go through the dorsal wall of pericardium, and
aorta and v. cava superior pass from above. The parietal lamina
of pericardium serosum passes into visceral lamina (epicardium).
In the area of arterial and venous transition zones the recessus of
pericardium are formed. Besides them we can distinguish more
significant gaps – pericardial sinuses. We can recognize sinus
transversus pericardii and sinus obliquus pericardii.
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