Download Internal Features Of Heart

Internal Features Of Heart
Learning objectives
At the end of lecture student will be able to :
Describe the part of heart.
Identify and describe the chambers and valves of the heart.
Discuss the different features of each chamber of heart.
Facts, location, & orientation
Oblique orientation
Apex points inferiosinister (down and left)
5th intercostal space
Base is superior near origins of great vessels
2nd intercostal space
2/3 lies left of the midline
For the most part
Anterior/inferior aspect of the heart
right atrium/ventricle
Posterior/superior aspect
left atrium/ventricle
Heart Features
 Chambers
 Right atrium
 Right ventricle
 Left atrium
 Left ventricle
• Valves
– Leaflet valves
• Tricuspid
• Bicuspid (mitral)
– Cusped (semilunar) valves
• Aortic
• Pulmonic
Right atrium
Auricle (ear)
Pectinate muscles (rough)
Sinus venarum (smooth)
Crista terminalis
Division between rough to smooth
Openings (ostia)
SVC/IVC/Coronary sinus
Fossa ovalis
Foramen ovale in fetus
Limbus
Right atrium
• The smooth-walled part, which is developed by the absorption of sinus venosus,
receives the opening of two venae cavae and the coronary sinus.
• The wall of the vestibule has a ridged surface and that of the auricle is rough.
• Both are developed from the embryonic atrium .
• The crista terminalis separates atrium proper and the auricle
Opening in Right Atrium
Superior vena cava
Inferior vena cava.
Opening of coronary sinus.
Atrioventricular (tricuspid) orifice.
Right atrium “valves”
Superior vena cava
No valve
Inferior vena cava
Eustachian valve
Incompetent in adult, directs IVC blood though Foramen ovale in fetus
Coronary Sinus
Thebesian valve
Prevents backflow into coronary sinus during atrial systole
RA
Right ventricle
Most anterior aspect of heart
Tricuspid valve (RA-RV)
Anterior/Posterior/Septal cusps (leafs)
Papillary muscles
Connected to cusps via Chordae tendinae
Contract to prevent Tricuspid valve regurgitation
Named same as cusps
Trabeculae carnae
Moderator band
RV
Right ventricle
• Supraventricular crest is in between the inlet and outlet components of the
ventricle
• The inlet component of the ventricle is rough, whereas the outlet portion, the
infundibulum, is smooth walled.
• The trabeculated appearance is because of muscular ridges and protrusions, which
are known as trabeculae carneae, and are lined by endocardium.
• The papillary muscles, which are inserted at one end onto the ventricular wall
give attachments to chordae tendineae on the free luminal end
Valve Structure
Dense connective tissue covered by endocardium
AV valves
chordae tendineae - thin fibrous cords
connect valves to papillary muscles
TRICUSPID VALVE
The atrioventricular valvular complex, in right ventricles, comprises of the orifice and
its associated anulus, the cusps, the supporting chordae tendineae of various types and the
papillary muscles.
The margins of this orifice are recognized as anterosuperior, inferior and septal, related
to the lines of attachment of the valvular cusps.
PAPILLARY MUSCLES
Anterior and posterior are two major papillary muscles in the right ventricle.
The third, smaller one is medial in position together with several smaller, and variable,
muscles attached to the ventricular septum.
Interventricular septum
Composed of muscular part and membranous part, strong obliquely placed b/w right and
left ventricles.
Muscular part –forms majority of IVS bulges into the cavity.
Membranous part ---part of fibrous skeleton of heart.
Semilunar valves
in the arteries that exit the heart to prevent back flow of blood to the ventricles
pulmonary semilunar valves
aortic semilunar valves
Pathologies
Incompetent – does not close correctly
Stenosis – hardened, even calcified, and does not open correctly
PULMONARY VALVE
The outflow from the right ventricle is guarded by semilunar pulmonary valve.
The three cusps are in part attached to the infundibular wall of the right ventricle and in
part to the origin of the pulmonary trunk.
The position of these cusps are two anterior cusps, right and left, and one posterior.
Left atrium
Ostia of 4 pulmonary veins
2 superior
2 inferior
Auricle
LA
Left atrium
The part of wall derived embryological from pulmonary vein.
Rough part of atrium derived from primitive atrium.
Trabeculated muscular part—pectinate muscle.
A semilunar depression in the interartrial septum indicates the floor of fossa ovalis.
Opening in the Left atrium
Four pulmonary veins.
Left AV orifice.
Left ventricle
Trabeculae carnae
Bicuspid (mitral) valve
Anterior/Posterior cusps
Papillary muscles
Chordae tendinae
Usually a greater number than the right, due to the increased pressures and strength
necessary to prevent regurgutation
Left ventricle
Walls are 2-3 times thicker from the right ventricles.
Walls are mostly covered with mesh of trabeculae carnea.
Cavity is conical.
Papillary muscles are anterior and posterior.
Smooth walled, non-muscular, superoanterior outflow part, the aortic vestibule---aortic
orifice and aortic valve
LV
Mitral Valve
The mitral valve has arrangement of cusps slightly different then the tricuspid.
This valve has as orifice with its supporting anulus, which provide attachment to cusps of
the valve.
There are 2 cusps anterior and posterior .
Aortic valve
Posterior to pulmonic valve
Just superior lies the Sinus of Valsalva
Helps to dampen aortic outflow and prevent cusps from adhering to walls of aorta
3 cusps
Posterior (non-coronary) cusp
Right
Left
Just superior to right and left cusps in the Sinus of Valsalva are the openings of the right
and left coronary arteries, respectively
Heart Valves
Tricuspid valve
RA – RV
Bicuspid valve
LA – LV
aka “Mitral valve”
Aortic valve
LV – aorta
Pulmonic valve
RV – pulmonary trunk
Conducting system
Inside the Heart…a review