Flashcards in Cardiovascular System Deck (130)
What is the daily output of blood from the muscular pumps?
What is the function of the aorta?
It is the main artery originating from the left ventricle that carries oxygenated blood away from the heart
What is the function of the left atrium?
Receives blood from the lungs and pumps into the ventricles
What is the function of the right atrium?
Receives blood from the venous circulation and pumps it into the ventricles
What is the function of the superior vena cava?
Returns deoxygenated blood from the systemic circulation to the right atrium of the heart
What is the function of the interior vena cava?
Carries deoxygenated blood from the lower and middle body into the right atrium
What is the function of the auricles?
They are a thin pouch if heart wall that helps the atrium to hold more blood by holding blood and contracting to pump
What is the peak pressure of the right ventricle?
What is the peak pressure of the left ventricle?
What is the peak pressure of the right atrium?
What is the peak pressure of the left atrium:
What are the 2 types of atrioventricular valves?
Bicuspid/mitral valve: left side
Tricuspid: right side
Describe the atrioventricular valves:
They are found between the atrium and the ventricles on the left (mitral) and right (tricuspid) sides of the heart. One edge is attatched to the wall of the heart and the other side is free so it is tethered by tendinous chords to prevent it from bursting upwards.
What is the purpose of chrodae tendine and papillary muscles?
To prevent the atrioventricular valves from going back up when the blood pushes against the valves after coming into the ventricles.
The 2 inlet valves (mitral and bicuspid) - atrioventricular are much larger than the outlet valves (aortic and pulmonary) - semilunar valves, why is this?
The inlets must be bigger because they are letting in the blood at a lower pressure so they need a larger diameter whereas in the outlet ones they are leaving at high pressure so they don't need a large diameter.
What are the 2 types of outlet valves - semilunar valves?
Describe how ventricular outlet valves/ semilunar work?
When blood leaves during ventricular ejection, it leaves the ventricle and flows up into the artery. The pressure of the blood trying to reenter the ventricles forces the free edges of the cusps together
Do semilunar/ventricular outlet valves need papillary muscles and tendinous chords, why/why not?
No because they are smaller so they don't need them
Where is the apex of the heart?
It is at the bottom and it points inferiorly, anteriorly and to the left.
What is the right border of the heart formed by?
The right atrium
What is the left border of the heart formed by?
The left ventricle
Describe the superior border of the heart:
It is the base border as it only attachment point of the heart and is tethered by blood vessels
Describe the pericardium:
It encloses the heart in a double walled bag. There is an inner layer (visceral pericardium) and outer layer (parietal pericardium) and they are both made by a single layer of squamous mesothelial cells. In the middle there is the pericardial space which is filled with serous fluid
What does the outer wall of the pericardium line?
The fibrous pericardium which is made up of collagen and is a tough fibrous sac.
Going from the blood to the outer pericardial sac, name all of the layers in between:
Blood, endocardium, myocardium (cardiac muscle), epicardium/visceral, pericardial space, parietal, fibrous, outer
What is cardiac temponade?
When the pericardial space has filled with blood
Describe how the valves of the heart are all connected to form the fibrous skeleton:
The fibres forming the tricuspid ring are incomplete and the pulmonary ring is absent. Both of these are associated with low pressure in the pulmonary pump. Fatty connective tissue is still present where the fibrous skeleton is incomplete.
Does the heart have nerves why/why not?
No it just has modified muscle that acts essentially as nerves.
Where is the AV node found?
Sitting in a hole in the fibrous skeleton