Cardiac Valves Flashcards
What is the purpose of cardiac valves?
To prevent the back flow of blood through the heart
What are the valves between the atria and the ventricles called?
The atrioventricular vales (AV)
Between the right atrium and the right ventricle there is a valve, what is it called?
The tricuspid valve
How many cusps does the tricuspid valve have?
3
How do the cusps of the tricuspid valve attach to the ventricular wall?
The 3 cusps are connected to Chordae tendineae and 3 papillary muscles
Which then attach to the ventricular wall
What produces the first heart sound?
The AV valve
closes during the start of ventricular contraction (systole)
What is the right atrioventricular valve also known as?
Tricuspid valve
What is the left atrioventricular valve also known as?
Bicuspid valve or mitral valve
What are the Chordae tendineae (tendinous cords) colloquially known as?
Heart strings
Where are the papillary muscles located?
The ventricles of the heart
How do the papillary muscles attach to the cusps of the AV valves?
Via Chordae tendineae
What does the contraction of the papillary muscles prevent?
Inversion or prolapse of the AV valves during systole (or ventricular contraction)
Where does the mitral valve lie?
Between the left atrium and the left ventricle
What is the mitral valve also known as?
Bicuspid valve, because it has two cusps
Where are the cusps of the mitral valve attached too?
Via the Chordae tendineae to two papillary muscles, projecting from the ventricle wall
What causes AV valves to open and close?
They open and close passively according to the change in pressure in the chambers
They open when the pressure in the atria is greater than that of the ventricles
What happens to the AV valves during ventricular contraction?
The pressure in the ventricles rises to greater that of the atria and the valves snap shut, preventing any back flow
What prevents the AV valves from opening upwards into the atria?
Chordae tendineae
tenuous cords that extend from the inferior surface of the cusps to small projections on the myocardium, little projections onto the wall of the ventricles called papillary muscles
How many semi-lunar valves sit next to each of the ventricles?
2
What is the semi-lunar valve coming from the right ventricle called?
The pulmonary valve
Where is the pulmonary valve located?
At the base of the pulmonary artery
How many cusps is the pulmonary valve composed of?
3
Is the pulmonary valve attached to any papillary
muscles?
No
What happens when the right ventricle relaxes?
Blood flows back into this ventricle from the artery
This flow of blood presses against each of the 3 cusps, and the valve closes, preventing the back flow of blood into the right ventricle
