Cardiovascular System Flashcards
What is the function of the cardiovascular system?
Circulating blood to allow:
* nutrient distribution ie. O2 and nutrients (AA, electrolytes)
* waste removal ie. CO2 and metabolic waste like urea (from protein metabolism) or uric acid (from nucleic acid metabolism)
* communication: transports chemical messengers like hormones (ie. thyroid hormones) from the area produced to the target tissues
* protection: circulates immune molecules and cells that can get to the site of infection or injury
When/ where do you find fully oxygenated blood?
- after gas exchange in the lungs (capillaries picking up inhaled O2 from alveoli and capillaries dropping off tissue cellular respiration produced CO2 from cells into the alveoli)
Where does deoxygenated blood come from?
the systemic circulation at gas exchange level of tissues (systemic capillaries) –> tissues that just dropped off O2 to tissue cells and picked up CO2 from tissue cells
Arteries ALWAYS take blood ____ from the heart , and it is normally _____ (oxygenation status)
What is the ONE EXCEPTION?
- Away
- oxygenated
- PULMONARY ARTERIES bc they carry deoxygenated blood to be oxygentated by the lungs
Veins ALWAYS take blood ____ the heart, and it is normally ____ (oxygenation status)
What is the ONE EXCEPTION?
- TO
- DEoxygenated
- PULMONARY VEIN brings oxygenated blood to the heart (freshly oxygenated by the lungs)
Characteristics of the arteries and veins
- high pressure blood flow, so there is lots of smooth muscle surrounding them
- low pressure blood flow, so low that they have **valves **to prevent backflow, and also have thin walls
General
Blood flow through the heart (also include oxygenation and deoxygenation status and valves)- visually have an image for it.
- [deoxygenated] Vena cava (superior and inferior; superior is blood from upper body and inferior is blood from lower body)
- R atrium
- Tricuspid valve
- R ventricle
- pulmonary valve
- pulmonary trunk and R and L pulmonary arteries
7.R and L Lungs- capillaries for gas exchange - [oxygenated] R and L pulmonary veins
- L atrium
- Mitral aka bicuspid valve
- L ventricle
- aortic valve
- aorta (blood to upper body and lower body)
- mneumonic for valves that are passed through for blood flow through the heart (also state what type of valve they are)
- What is the function of the valves?
- Toilet- Tricuspid [AV valve]
- Paper- Pulmonary [semilunar valve]
- My- Mitral aka bicuspid [AV valve]
- Ass- Aortic [semilunar valve]
- prevent backflow of blood
Label an image of the heart (cover the labeled parts that are in my Dr. Yu main notes)
- How many layers does the heart have and what are the layers?
- What is endocardititis and what is one way one can get it?
- 3: endocardium, myocardium,epicardium
- inflammation of the endocardium from sharing needles
Left ventricle is [___] and [______] than the right ventricle because [_______]
- LARGER
- THICCER
- it needs to pump blood to the WHOLE body
atria is recieving blood so it has thinner walls than the ventricles
The atria have ___ walls compared to the ventricles
thinner
Describe the pulmonary circuit of blood.
What is the most general function of this circuit?
- deoxygenated blood eventually turns into oxygenated blood
- R side to the L side
- R ventricle –> pulmonary Artery –> R and L lungs –> pulmonary Veins –> L atrium
- pumps blood to the lungs to be oxygenated
Name the 2 places where gas exchange occurs
- lungs b/w the pulmonary capillaries and alveoli
- tissues b/w systemic capillaries and tissue cells
Describe the systemic circuit of blood.
What is the most general function of the circuit?
- oxygenated blood –> deoxygenated blood
- L side to R side
- L ventricle –> aorta (highest pressure ) –> body tissues –> small arteries –> arterioles (regulate flow) –> systemic capillaries (gas exchange) –> venules –> veins –> vena cava (lowest pressure) –> R. Atrium
Systemic Circuit
Which part of the systemic circuit has the highest pressure? Lowest pressure?
- aorta; vena cava
What type of blood vessel is a major regulator of blood flow?
arterioles- they have the greatest impact on BP. When we talk about vasoconstriction/ dilation, we are talking about these things.
Example: when excerise, arterioles to skeletal m. dilate for more blood flow and O2 and the kidney’s arterioles constrict to decrease blood flow to the kidney’s
Coronary Circuit
Coronary Artery supplies [_____] blood to the [_____]
- oxygenated
- heart muscle (myocardium)
Coronary Circuit
Coronary Vein supplies [] blood to the []
- deoxygenated
- R atrium
Explain the coronary circulation
in main document flow chart under “coronary circuit”
- What is a common artery that can be blocked to cause a heart attack?
- What part of the heart does that artery supply?
- Where does this artery branch off of?
* Left Anterior descending (interventricular) artery
* cardiac muscles of the left ventricle
* Left coronary artery, which is from the aorta.
heart dz
- How does one get a heart attack?
- What is another name for heart attack?
- artery is blocked (ie. by atherosclerotic plaque) –> no blood with O2 and energy to cardiac muscle cells –> cells become ischemic and damaged and die fast –> not enough power to pump blood to the body –> heart attack
- myocardial infarction
Conduction System of the Heart
The conduction system of the heart causes ____ atria to ____ and then ____ ventricles to ______ from the ______ in order to move the blood through the heart
- both; contract; both; contract; bottom up
Conduction System of the Heart
What allows the heart to contract on its own in an orderly and sequential manner?
Where is this thing located and what does this thing do?
- SA node cardiac pacemaker cells in the R atrium
- it can generate its own electrical impulses/ action potentials to control heart contractions.
Explain the order of conduction system of the heart
- SA node– both atria contract
- AV node- both atria contract
- Bundle of His
- R and L Bundle Branches- bottom of ventricles contract
- Purkinjie Fibers -top of ventricles contract
where it contracts that i put is approximate.
What happens if the AV node is damage?
AV heart block –> ventricles still contracting at 40-60 bpm bc of the autorhythmaticity of the bundle of His and the atrium signals are not reaching the ventricles
ECG
- What does the P wave represent?
- What does the QRS complex represent?
- What does the T wave represent?
- atrial depolarization
- ventricular depolarization
- ventricular repolarization
How can the SA node beat be modified from what it normally intrinisically is?
- parasympathetics: vagus delivers Ach to slow heart down (dec HR) and dec contractility (force of contraction)
- sympathetics: T1-L2 delivers NE, which binds to beta 1 adrenergic receptors on cardiac pacemaker cells of SA node to inc action potentials and inc HR and bind to beta 1 adrenergic receptors on cardiac muscle cells to inc Ca and inc contracility
- hormones: epi and thyroxine can speed up HR by i assume inc action potentials fired from node.
beta blockers dec HR and force of contraction, so great for CHF (and high BP-3rd -4th choice for BP)
Heart sounds
How are the heart sounds normally heard produced?
CLOSING of the heart valves, which are governed by pressures in the ventricles as well as ventricular contraction and relaxation.
- Explain Lub.
- What is another name for Lub?
AV valves(tricuspid and bicuspid aka mitral) are snapping shut *when R and L ventricles are ready to pump blood into their respective vessels aka DURING ventricular systole/ contraction (so high ventricular pressure)to prevent backflow of blood to the atrium.
- Explain Dub.
- What is another name for Dub?
- Semilunar valves (pulmonary and aortic) are snapping shut to prevent vetricular blood that just exited the ventricles from going back to the ventricles aka at the END of ventricular contraction and during ventricular diastole/ relaxation (so low ventricular pressure) and subsequent atrial systole that is supplying blood to the empty ventricles
- S2
When are the AV/ SL valves open?
- low pressure and high pressure, respectively, in the ventricles
What is systole?
- contraction(ventricular more commonly thought of) ; pressure inside the artery (aorta) when the heart contracts and pumps blood through the body.
- part of cardiac cycle where the heart expels blood [ force required to pump blood out of the ventricles]
What is the normal blood pressure and why is systole normally higher?
- 120/80
- higher bc left ventricle takes alot of force to pump blood to the WHOLE body
What is diastole?
- relaxation (more commonly thought of as ventricular); pressure inside the artery when the heart is at rest and is filling with blood.
- part of the cardiac cycle where the heart refills with blood [ during ventricular diastole, atria can contract and push blood into the ventricles]
Explain general cardiac physiology and valve status.
- isovolumetric relaxation- atrial diastole (blood flowing intro atria) and early ventricular diastole (muscles itself relaxing) [all valves are CLOSED] [ AV valves closed bc pressure in ventricles is still too high] [SL valves closed bc pressure in ventricles are too low to keep it open]
- Ventricular Diastole- late: filling of the ventricles [ AV valves OPEN bc low pressure in ventricles] [ SL valves CLOSED bc low pressure in ventricles]
- Isovolumetric contraction [ all valves are CLOSED]
- Ventrciular Systole
*venctricular contraction [pressure in ventricles builds and all valves are CLOSED esp since chordae tendonae seals AV valves shut]
* ventricular ejection [AV valves CLOSED][ SL valves OPEN bc high enough pressure to overcome the afterload from the outside arteries to eject blood out]
- What is end diastolic volume?
- What is another name for EDV?
- the blood in both of the ventricles after it is done filling
- pre-load, which is the pressure on ventricle walls during filling phase
- normally is 120 mL
Heart dz’s
Murmurs
- indicates a valvular problem bc sound is from blood swishing and backflowing
What is stroke volume?
- whatever is pumped out of the heart after 1 full contraction of atria and ventricles
- EDV-ESV (~70 mL)
What is end systolic volume?
- blood left over after ventricular ejection is complete
- ~ 50 mL of blood
What can cause decreases in stroke volume?
- heart muscle damage (ie. heart attach) –> scarred collagen fibers –> dec compliance –> dec filling –> dec EDV
- dilated cardiomyopathy= overstretched heart
- all of these can dec ejection fraction
What influences the EDV?
- total blood volume (total amount of blood in the body ie . hydration status)
- venous return (how fast blood is coming back to the heart) (increased by exercise)
- compliance of the heart (stretch of the heart/ myocytes)
Heart Diseases
HTN
Heart Dz’s
Atherosclerosis
plaque build up in the artery walls (in pt with vascular risk factors like > 45, HTN, DM, hyperlipidemia, smoker, alcoholic that exposes them to chronic endothelial injury from high blood turbulence) –> narrowing of the artery
heart dz
Stroke
a brain attack aka no blood to the brain.
* clotting stroke- ischemic (athersclerotic/ thrombotic from ruptured plaque and thrombi form to block large vessel-pale infarct; embolic from afib emboli clotting MC MCA- can lead to hemorrhaghic infarct; lacunar from HTN and DM hyaline arteriosclerosis narrowing small arterioles lumen that supply deep brains structures)
* bleeding stroke- hemorrhaghic from a ruptured blood vessel like a ruptured aneurysm, which are thin sac balloon like outpouchings due to weakened artery walls due to lacking a media layer of smooth muscle of artery
heart dz
Arrhythmia
- abnormal heart electrical impulses from malfunction of heart electrical system
BP regulation
Explain RAAS
in RAAS drawing document in ipad
RAAS
What does angiotensin 2 do to blood vessels (arterioles)?
vasoconstricts them –> increases peripheral resistance –> inc BP
- What hormone does angiotensin 2 trigger the adrenal’s to make?
- What specific part of the adrenal’s is this hormone made?
- What is the function of this hormone?
- aldosterone
- cortex
- inc Na (and so H2O) reabsorption in the kidneys (late distal tube and collecting duct) –> inc blood volume –> inc BP
- What hormone does angiotensin 2 trigger the pituitary gland to make?
- What specific part of the pituitary is this hormone RELEASED from??
- What is the function of this hormone?
- ADH/ vasopressin
- posterior (MADE in the PVN of hypothalamus)
- inc H2O reabsorption at the kidneys (late distal tube and collecting duct) –> DIRECTLY inc blood volume –> inc BP
Meds to lower BP
- first choices: thiazides (diuretics); ACE, ARBs, Ca channel blockers
- 3rd/4th choice: beta blockers
