Week 8 - Study Guide Flashcards
What size is the heart?
Fist sized
What is the heart protected by and is double layered?
Pericardium - double sac
What are the two layers of the pericardium?
- Fibrous
- Serous
What is the function of the Fibrous layer of the pericardium?
- Limits overfilling to keep the heart successful in pumping.
(protects and prevents overfilling) - Fibrous CT helps protect the heart from outside sources of infection and irritation
- Protects the heart from overfilling
Under certain physiological conditions - you could have the risk of overstretching/overfilling.
If that happens to the heart - it will reduce the functionality of the pumping of the heart.
What is the function of the serous layer of the pericardium?
It has two layers itself
Serous Pericardium
fluid separates two more layers
in between the two layers is fluid that protects from friction.
2 layers are:
1. Parietal layer
2. Visceral layer
Parietal Layer of the Serous Pericardium
- This layer is more exterior
- Is attached to fibrous sac of the pericardium
Visceral Layer of the Serous Pericardium
AKA epicardium
Internal layer - on surface of the heart
Two layers of the Serous Pericardium
- Parietal
- Visceral
Pericardial Fluid
- Located between the 2 layers of Serous Pericardium.
- There has to be fluid in between the parietal and visceral layers in order to assist the normal movement of the heart.
- Heart is highly mobile organ
- Pumping blood all of the time
- Fills and empties repeatedly
Having two sticky layers (parietal & Visceral) of the membrane
1. the fluid is going to help the two layers slide past each other
2. to avoid friction
3. or inflammation
Pericarditis
- Inflammation, damage, injury, or infection of the pericardium
Negative impact associated with inflammation and infection of the pericardial layers.
That could be damaging because may build-up of fluids, irritations, inflammation on the heart is going to negatively impact its ability to act as an appropriate pump
Name the three layers of the heart:
- Epicardium
- Myocardium
- Endocardium
Epicardium
- The visceral layer of the serous pericardium
- Often fatty in the elderly
- Outer Layer
Myocardium
- muscular part of the heart (cardiac muscle)
- Connective Tissue
Why & where does the myocardium have variable thickness?
- Contractile muscle tissue in the heart - in the ventricles.
Variable thickness Where?
1. Atriums are not very thick
2. Right ventricle is a bit thicker
3. Left ventricle is very thick
Variable thickness WHY?
1. to allow for the pumping of the blood to all the various locations that it needs to go
2. needing different amounts of muscle strength to pump blood out to the lungs vs the systemic circuit
Endocardium
Blood vessels in body all have squamous epithelium and is connected to your heart.
Endocarditis
Inflammation in the heart (endocardium)
Possible causes of endocarditis
- contaminated needles which could cause an infection through the circulatory system - which could result in endocarditis
Endocarditis could lead to
- Valve damage
- emboli
Valve Damage
the pumping of the heart would be impaired
Emboli
could end up with traveling blood clots which could lodge in:
1. the heart - causing a heart attack
2. lungs - causing a pulmonary embolism and pulmonary edema
3. Brain - causing a stroke
Myocardium has a unique set of features within the ventricles:
Papillary Muscles
Function - to help hold the ventricular valves in place and keep them from inverting.
They hold the chordae tendineae which are attached to the AV valves and anchored by the papillary muscles to the myocardium.
Ensuring that the valves do not get pushed backwards into the atria as the ventricles contract
Heart Features
- Atria & Ventricles
- AV valves - tricuspid & bicuspid
- Semilunar valves - pulmonary & aortic
- Interatrial septum
- Atrioventricular Septa
- Interventricular septum
Another name for bicuspid valve
Mitral
How many cusps do the tricuspid have?
Right side = 3 cusps
How many cusps does the bicuspid (mitral) valve have?
Left side = 2 cusps
Names of the AV valves
- tricuspid valve
- bicuspid (mitral) valve
Names of the Semilunar Valves
- Pulmonary semilunar valve (to the lungs)
- Aortic semilunar valve (to the body)
Interatrial septum
a barrier, in between atriums