Thorax 3 - Internal Heart Flashcards
What is the name of the valve that separates the right atrium from the right ventricle?
Tri-cuspid
What is the name of the valve that separates the left atrium from the left ventricle?
Bi-cuspid/Mitral
Name the valve present at the opening of the aorta and state how many cusps there are.
Semi-lunar valve - aortic valve
3 cusps
Through which structure does deoxygenated blood pass through when passing from the heart muscle to the right atrium?
Coronary sinus
What is the function of the foramen ovale in an embryo?
So that blood can pass straight from the right atrium to the left atrium
What does the foramen oval develop into upon birth?
Fossa Ovalis
During systole, what is the role of the papillary muscles and the chordae tendiniae?
Prevent cusp eversion
How are the cusps opened?
Pressure exerted by the blood
Where are the origins of the right & left coronary arteries?
Right and left cusps (not posterior) of the aortic valve
What separates the atria and the ventricles
Fibrous muscle
What is the myocardium?
The heart muscle
What is the endocardium?
The endothelium that lines the chambers and valves of the heart
What is the pericardium?
The heart wall
Name the 3 vessels/structures that bring deoxygenated blood into the right atrium.
SVC
IVC
Coronary sinus
Name some features of the anterior right atrial wall.
Trabeculation
Auricle
Musculi pectinati
Crista terminalis
What is the crista terminalis?
The border which separates the ridged from the smooth section of the atria
What is the limbus fossa ovalis?
The rim around the fossa ovalis
What are the musculi pectinati?
Muscular ridges which arise from the crista terminalis
Between which two chambers does the foramen ovale (embryo) or fossa ovalis (post natal), lie?
Right atrium & Left atrium
What type of trabecula is present in the walls of the right ventricle?
Septomarginal trabecula
How many papillary muscles are present in between right atrium and right ventricle?
3
Describe active competence.
The papillary muscles and chordae tendineae prevent cusp eversion during systole
What are the three tri-cuspid valve cusps called?
Anterior
Posterior
Septal
What is the relationship between papillary muscles, chordae tendineae and the cusps?
Each papillary muscle sends 2 chordae tendineae to each cusp
What is the function of the musculi pectinati?
Provide some power of contraction in the atria
What are the names given to the 3 papillary muscles and the 3 cusps at the tricuspid valve?
Anterior
Posterior
Septal
What is the septomarginal trabecular also known as?
The moderator band
What is the role of the papillary muscles and the chordae tendinae?
Prevent cusp eversion during systole
What are the names given to the 3 cusps at the pulmonary semi-lunar valves?
Right
Left
Anterior (coronary)
What are the names given to the 3 cusps at the aortic semi-lunar valves?
Right
Left
Posterior (non-coronary)
What is passive competence?
No contraction of any papillary muscles, but due to elastic recoil in the pulmonary trunk and aorta. A pressure difference causes the blood to get between the cusp and wall, forcing the cusps closed (semi-lunar valves)
Why does the wall of each ventricle becomes smooth near its outflow?
To create laminar blood flow into the pulmonary trunk and aorta
Describe the relationship of the pulmonary trunk and the aorta with regard to location and connections.
Pulmonary lies inferior to the aortic arch and is liked to the aorta via the ligamentum arteriosum
What are the names of the 4 pulmonary veins?
Superior
Inferior
Right
Left
Where can the auricle be found on the left atrium?
Left cardiac surface
Blood enters the LV via the…
Aortic vestibule
What are the two cusps of the mitral valve?
Anterior
Posterior
What is active competence?
Use of papillary muscles to prevent eversion (atrioventricular valves)
Aortic sinuses give rise to the coronary arteries. Where can the aortic sinuses be found?
Just superior to the right and left cusps of the aortic semi-lunar valve
What is the function of the cardiac (fibrous) skeleton?
This supports valves and myocardium and importantly, it electrically separates the atria from the ventricles.
What is the only route of conduction between atria and ventricles?
Bundle of His
What causes the 1st heart sound at the start of systole?
Closure of the mitral and tricuspid valves
What causes the 2nd heart sound at the end of systole?
Closure of the aortic and pulmonary valves
Where can the mitral valve be ascultated?
Apex - 5th left intercostal space, mid clavicular line
Where can the tricuspid valve be ascultated?
4th or 5th left intercostal space, just left of sternum
Where can the aortic valve be ascultated?
2nd right intercostal space
Where can the pulmonary valve be ascultated?
2nd left intercostal space
List the corners of the heart.
5th left intercostal space, mid clavicular line
6th right CC
3rd right CC
2nd left CC
