Chambers of the Heart Flashcards
The heart is divided by
vertical septa
The heart is divided into
four chambers ( the right and left atria and the right and left ventricles)
right and left atria شو مالهم
The right atrium lies anterior to the left atrium
right and left ventricles شو مالهم
The right ventricle lies anterior to the left ventricle
The cavity of right atrium is divided
into
2 continuous spaces.
The separation between these 2
spaces marked
Externally
Internally
The separation between these 2
spaces marked Externally by
a vertical groove (sulcus terminalis) extending from the right side of SVC to
the right side of IVC.
The separation between these 2
spaces marked Internally
this division is indicated by a smooth muscular ridge (crista terminalis).
spaces of cavity of Right Atrium
Space posterior to crista terminalis
Space anterior to crista terminalis
Space anterior to crista terminalis
(Atrium proper)
Space posterior to crista terminalis name
(sinus of venae cavae)
Space anterior to crista terminalis includes
Right auricle.
Space anterior to crista terminalis
(Atrium proper) characteristic
Rough and covered by bundles of muscle
fibres (musculi pectinati).
ØThe blood leaves right atrium to
right ventricle via
tricuspid valve.
Space posterior to crista terminalis
(sinus of venae cavae) characteristic
Has smooth, thin walls.
the right atrium separated from left atrium by
The interatrial septum
The interatrial septum has an oval depression called
Fossa ovalis
The margin of oval depression is called
Anulus ovalis (limbus of fossa ovalis)
The fossa ovalis marks the location
of the embryonic
foramen ovale
foramen ovale is an important part of
fetal circulation
→ allows oxygenated blood (coming to right atrium through IVC) to pass directly to the left atrium and so bypass the lungs, which are nonfunctional before birth
Openings in right atrium
SVC IVC Coronary sinus Right atrioventricular orifice Openings for small veins.
SVC Opening
It returns the blood to the heart from the upper half of the body.
IVC Opening
it is guarded by a rudimentary, nonfunctioning valve.
Coronary sinus Opening
has a well-defined valve
Right atrioventricular orifice Opening lies anterior to
IVC opening
Right atrioventricular orifice is surrounded
by
a fibrous ring which gives attachment to the tricuspid valve.
The right ventricle communicates with the right atrium through the
atrioventricular orifice.
The right ventricle communicates with the pulmonary trunk through the
pulmonary orifice
infundibulum (conus arteriosus).
As the cavity approaches the pulmonary orifice it becomes funnel shaped,
wall of right ventricle is
thinner than that of left ventricle
walls of right ventricle contain
muscular irregular projections called trabeculae carneae
type of papillary muscles
- Anterior papillary muscle
- Posterior papillary muscle
- Septal papillary muscle
Trabeculae carneae with one end attached to
ventricular surface
papillary muscles
Trabeculae carneae with one end attached to ventricular surface
Each papillary muscle is attached to
the cusps of tricuspid valve by tendinous threads called chordae tendineae.
chordae tendineae.
Each papillary muscle is attached
to the cusps of tricuspid valve by tendinous threads
Cavity of right ventricle
سلايد 23
Left atrium of the heart forms
the greater part of base of heart.
Left atrium of the heart wall is
smooth except for small musculi pectinati in the left auricle
Left atrium of the heart Receives
4 pulmonary veins which have no valves.
Left atrium of the heart Sends blood to
left ventricle through the left atrioventricular orifice which is guarded by mitral valve
The interatrial septum separates
Rt & Lt atria
depression in interatrial septum
valve of foramen ovale
Left ventricle of the heart wall is
thicker than that of right ventricle.
Left ventricle of the heart wall contains
- trabeculae carneae.
2. 2 large papillary muscles (anterior & posterior)
Left ventricle of the heart receives blood from
left atrium through left atrio-ventricular
orifice which is guarded by mitral valve.
ØThe blood leaves Left ventricle of the heart
to the ascending aorta through the aortic
orifice
interventricular septum separates
the right & left ventricles.
interventricular septum
■ a muscular part.
■ a membranous part.
2 large papillary muscles (anterior & posterior) are attached by
chordae tendineae to cusps of mitral valve
