Heat and Neck Vessels systems Flashcards
Precordium
Mediastinum
What are the positions of the heart
-what produces the apical pulse
Precordium- the area on the anterior chest OVER the heart and great vessels
Mediastinum- area in the chest that contains the heart
Heart Position:
- The top (wider) area of the heart is the base
- The bottom (pointed) area is referred to as the apex
The apex beats against the chest wall– producing the apical pulse
Landmarks: The heart
Where is the heart located
What is the apex location
Heart Location:
Top to bottom:
-2nd– 5th intercostal space (ICS)
Left to Right:
-Right border of the sternum to the LEFT mid-clavicular line
Apex Location:
- 5th intercostal space
- Between mid-sternal and mid-clavicular lines
What are the three layers of the heart and what fluid is there
Pericardium
- Tough, fibrous, sac that surrounds and protects the heart
- Between the layers is pericardial fluid (this ensures a smooth, FRICTION FREE movement of the heart muscle)
Myocardium
-Muscular wall of the heart. Responsible for the pumping action of the heart.
Endocardium
-Thin layer of endothelial tissue that lines the heart chambers and valves
Heart Valves
What is a valve
what is its purpose
how do they open
what are the four valves
Valves- separate the chambers
-Act as swinging doors (unidirectional or one-way only)
Purpose: prevent backflow of blood
They open PASSIVELY based on changes in the pressure gradient in the heart
4 valves in the heart:
- Right Atrioventricular (Tricuspid)
- Left Atrioventricular (Bicuspid/Mitral)
- Right Semilunar (Pulmonic)
- Left Semilunar (Aortic)
AV valves
What do they separate
What are their names
When do they open
When do they close
What are Chordae tendineae and what do they do
What happens when the ventricles are relaxed 3
what happens when the ventricles contract 3
Two AV valves (atrioventricular) separate the atrium and ventricles:
- The RIGHT AV valve is the tricuspid valve
- The LEFT AV valve is the BICUSPID or mitral valve
- The AV valves OPEN during the heart’s filling phase so the blood from the atria can fill the ventricles
- The AV valve CLOSE after filling to prevent a back flow into the atria.
Chordae tendineae are collagen fibres that anchor the AV valves to papillary muscles which are embedded in the ventricle floor
When the ventricles are relaxed
- Chordae tendineae are slack
- Valves are open
- Blood fills the ventricles
When the ventricles contract
- Blood in the ventricles push the valves closed
- The papillary muscles contract & tighten the chordae tendineae (prevents the valve leaflets from flipping back up into the atria)
- Blood is ejected from the ventricles
Semilunar Valves
What do they separate
what are their names
When do they open
Where does the right and left side of your heart send blood
Two semilunar (SL) valves separate the ventricles and the greater vessels:
The RIGHT semilunar valve is the pulmonic valve
-Between right ventricle & pulmonary artery
The LEFT semilunar valve is the aortic valve
-Between left ventricle & aorta
They open when the heart pumps to allow blood to be ejected from the heart (either to the lungs or to the body)
Right side of your heart is sending blood to our lungs
Left side of your heart is sending blood to the aorta and then out systemically to the rest of the body
What are the great vessels, where are they located
What does each do and what kind of blood
When is the only time an artery carries de-oxygenated blood and when does a vein carry oxygenated blood
What is the largest artery in the body
what are the 4 divisions of the 4rth
- Superior & Inferior Venae Cavae- returns deoxygenated blood to the RIGHT Atrium
- Superior- from above
- Inferior- from below - Pulmonary Artery- takes deoxygenated blood to the lungs from the RIGHT ventricle
- Leaves right ventricle and bifurcates (divides into 2)
- Carries deoxygenated blood to the lungs, where it then gets oxygen
- *This is the ONLY time that an artery will carry de-oxygenated blood - Pulmonary Veins- take oxygenated blood to the LEFT atrium from the lungs
- *This is the ONLY time that a vein will carry oxygenated blood - Aorta- takes oxygenated blood to the body from the LEFT ventricle
- Largest artery in the body
4 divisions: Ascending- coronary arteries Arch- head and arms Thoracic- lungs and mediastinum Abdominal- abdomen and lower limbs
Circulation of blood
What makes up the CV system
CV system is a double pump with 2 divisions
Division #1 – pulmonary circulation
RIGHT SIDE OF HEART → circulates to the lungs
Division #2 – systemic circulation
LEFT SIDE OF HEART → circulates to the body
Pulmonary Circulation
What side does it work on
Where does it take blood
and what does it do
Division #1 – Pulmonary circulation
RIGHT SIDE OF HEART → circulates to the lungs
Pulmonary artery carries DEOXYGENATED blood to the lungs, where the blood picks up O2 and releases CO2 in CAPILLIARIES
Systemic Circulation
What side does it work on
Where does it take blood
Division #2 – Systemic circulation
LEFT SIDE OF HEART → circulates to the body
OXYGENATED blood travels FROM THE LUNGS in the PULMONARY veins to the LEFT atrium
This oxygenated blood travels FROM the LEFT ventricle to the AORTA and out to the body
What is the direction of blood flow 5
- DEOXYGENATED travels from superior & inferior vena cava into the RA
- RA through the Tricuspid valve into the RV then through the Pulmonic valve into the Pulmonary artery and to the lungs
- Oxygenated blood from the lungs travels through the Pulmonary veins back to the LA
- From the LA through the Mitral Valve into the LV
- LV through the aortic valve and into the aorta and to the abdomen and lower extremities
What is the cardiac cycle
What are the 2 phases
Why does blood flow occur
Why does the valves open
Cardiac Cycle- the rhythmic movement of blood through the heart
2 phases:
Diastole- Ventricular relaxation
Systole- Ventricular contraction
*Note: blood flow occurs due to pressure changes
When a chamber contracts the valves open
Cardiac Cycle Diastole
What is diastole
what are the 2 stages
When does atrial systole occur
What initiates the cycle
(Rapid filling [protodiastolic] - slow filling -presystole)
Diastole- Ventricles relax and fill with blood
-The AV valves are OPEN → blood rushes into ventricles
- Passive filling- Pressure in the atria is HIGHER than in the ventricles
(a. k.a. early or protodiastolic filling) - Active filling- Atria contract to eject the remaining blood into ventricles
(a. k.a. atrial systole, presystole or atrial kick)
Note: ATRIAL systole occurs during VENTRICULAR diastole
Alternating pressure
Cardiac Cycle: Systole
What is systole
What are the 8 stages
Systole- Ventricles contract and pump blood out
1.Pressure builds in ventricles (due to blood entering from the atria)
2.AV valves CLOSE (to prevent backflow of blood)= S1 occurs
BEGINNING OF SYSTOLE
- All 4 valves are closed for a brief time
- Ventricular CONTRACTION occurs
- Pressure in ventricles exceeds the pressure in the aorta
- Semilunar valves OPEN (blood ejected)
- Ventricle begins to RELAX
- Blood flows backwards towards the ventricle & fills the semilunar cusps - Semilunar valves CLOSE= S2 occurs
- END OF SYSTOLE
Cardiac Cycle Concepts
What is isometric relaxation
when does is occur
What is isometric contraction
When does it occur
Why do we have off sounds in the heart
What is blood pressure
Isometric Relaxation
- Occurs in Diastole
- All FOUR valves are closed and atria are filling once again
Isometric Contraction
- Occurs in Systole
- All FOUR valves are closed. Occurs just before ventricular contraction
Right side of the heart needs less pressure to go to lungs (timing slightly later)
Left side needs to send to rest of the body
That’s why we have the off sounds
BP= systolic pressure OVER diastolic pressure:
-Maximum pressure on the artery during systole
OVER Resting pressure during diastole
