5 Flashcards
How many heart valves
4
2 on each side (paired)
Valves on left side of heart
Atrioventricular valve - between atrium and ventrical
Semilunar valve - controls flow from ventricular chambers to the outflow artery (aorta)
Atrioventricular AV valves function:
Prevent blood returning to atria during ventricular contraction (when pressure goes up in ventricular chamber)
- can only go from atria to ventricle
We refer the the atrioventricular (AV) valves on the right side as
Tricuspid valve ( has 3 distinct flaps)
We refer the the atrioventricular (AV) valves on the left side as
Bicuspid (mitral) valve
Location of the 4 valves and how they look in sysitle and diastole
-pumpunary + tricuspid RIGHT
-aorta + bicuspid LEFT
Leaflets also show which one’
AV ones are bigger
Why does left chamber look smaller
Due to the rotation within the chest cavity
Operation of atrioventricular valves (Diastole and systole)
DIASTOLE
Filling phase - blood flows through valves
- blood fills chambers
- heart is pulsitile pump
- AV valve is open
SYSTOLE (ventricular)
- AV valve is close (pushed shut from the pressure so blood not pushed back the way it came)
- ventricles are contracting
- pulmonary valve (semilunar valve) is then opened
Va;ves are opened and closed during…
Different phases of the cardiac cycle
Function of semilunar valves
Prevent blood returning to ventricles, once ejected, during filling (diastole)
- once ventricles constrict and push blood into arteries - semilunar valves stop blood from flowing back after the heart relaxes
Semilunar valveless on the right side are revered to as
- pulmonary valve, 3 cusps
(Valves that opens to the pulmonary circulation)
Pushed open during ventricular systole (blood flows out of heart)
Semilunar valve on the left side is called
Aortic valve - 3 cusps
Pushed open during ventricular systole (as blood flows out of heart)
Closed as blood starts to flow back
Intraventricular septum
Seperates left and right ventricle
Papillary muscles and chordate tendineae and AV valve leaflet attachment
- papillary muscle is attached to chordate tendineae
- chordate tendineae is attached to AV valve leaflet
- papillary muscle dont pull leaflet open, they control the rate at which they close
ONLY IN AV
Why do semilunar valve not need chordate tendineae
- aortic and pulmonary valve done need them because leaflets are smaller and dint get exposed to as much pressure - support themselves
First supply path of the Cardiac circulation (ALL TLAKING)
- coronary arteries (comes from a branch of the ascending aorta, runs over pericardial layer, within a grove between the right atrium and right ventricle and run around groove into posterior of heart that will branch along the way over the epicardium and smooth branches will go down into ventricle
- heart has lots of muscle in myocardial layer - needs lots of blood supply - first branches on systemic system come back and bring oxygenated blood from aorta straight back to heart