Lecture 23: Intro to Cardiovascular System and Cardiac Anatomy

Question 1

What is Heart Failure?

Answer 1

It is when the heart muscle is unable to contract optimally to pump blood at a rate sufficient to meet the requirements of metabolizing organs

Question 2

What are some common symptoms of heart failure?

Answer 2

-Congestion in the lungs results in breathlessness
-fatigue
-swelling of the ankles and legs
-enlargement of liver

Question 3

What is MI (Myocardial Infarction)?

Answer 3

It is loss of heart muscle due to stoppage of blood flow

Question 4

What are some risk factors of Post-MI patients moving into heart failure?

Answer 4

-Genetics
-Smoking
-Gender
-Diet
-Personality
-Stress
-Social stratum
-Alcoholism
-High BP
-Diabetes
-Idiopathic primary cardiomyopathy
-Viral infection of heart
-Cardiac valve diseases and associated abnormalities

Question 5

What are the three components of the Circulatory system

Answer 5

-The heart
-The blood vessels
-The blood itself

Question 6

What is the function of the heart in the circulatory system?

Answer 6

A pump that serves to pressurize the arterial tree

Question 7

What is the function of the Blood vessels in the circulatory system?

Answer 7

Serves as the delivery mechanisms for blood as it moves away from the heart and for its return to the heart

Question 8

Which vessel carry blood away from the heart and which vessel carries blood towards the heart?

Answer 8

Away from the heart-Arteries
Towards the heart-Veins

Question 9

What are the two types of circulations ?

Answer 9

Pulmonary circulation
Systemic circulation

Question 10

What does the Pulmonary circulation carry?

Answer 10

Carries blood between the heart and the lungs

Question 11

What does the Systemic Circulation carry?

Answer 11

Carries blood from heart to all the peripheral organ system. Thus the heart functions as a dual parallel pump

Question 12

Where is the heart located?

Answer 12

Mid chest between the sternum and the vertebrae

Question 13

what are the upper and lower chamber called and what are their functions?

Answer 13

Upper chambers are Atria and the the receive blood returning to the heart
Lower chambers are ventricles which pump blood from the heart out

Question 14

What are the two halves of the heart separated by and what other role does it have besides contributing to cardiac pump function?

Answer 14

It is separated by the ventricular septum and the wall prevents the mixing of the blood from the low oxygenated blood in the right and the highly oxygenated blood in the left side

Question 15

what is the blood movement like in a systemic return?

Answer 15

The blood enters the RA via the vena cavae and its O2 poor blood and flows from the RA to RV. Which is then pumped out via the Pulm.Artery to the lungs where its oxygenated.

Thus the right side of the heart pumps into the pulmonary circulation

Question 16

What is the blood movement like when it goes from the lungs to the Aorta?

Answer 16

in the lungs blood loses CO2 and acquires O2 before returning to the LA via the Pulm,Vein
Then the O2 rich blood moves from LA to the LV to the aorta and thus to the systemic circulation

Thus the left side of the heart handles the systemic circulation

Question 17

How does each capillary bed receive a fresh supply of blood?

Answer 17

When the Aorta carries blood away from the LV and then the output from the LV is distributed to each relevant capillary bed.

Question 18

At what pressure and volume does each side of the heart pump out?

Answer 18

They both pump equal volumes of blood per unit time but the left side does it at a pressure of 120mmHg max systolic and right side does it at 25-30 mmHg max systolic pressure

Question 19

Between the RV and LV which one does more work and why?

Answer 19

The LV because it is bigger in size compared to the RV and it does more work as it does it at a higher pressure against a higher resistance system

Question 20

What do cardiac valves allow and how many are there?

Answer 20

They allow for the unidirectional (forward) flow of blood for efficient pump action. they open in response to pressure and are one way. Backward pressure forces the valves closed.
There are 4 valves

Question 21

What do the Right and Left atrioventricular valves do?

Answer 21

Allow for movement of blood from the atria to the ventricles during filling and serve to keep blood in the ventricles when they contract and the rising ventricular pressure forces them closed

Question 22

Which of the Right and Left AV valves are tricuspid and mitral?

Answer 22

Right AV=Tricuspid
Left AV=Mitral

Question 23

What is the heart wall composed of?

Answer 23

Spirally arranged cardiac myocytes(muscle fibers). They form an electrical syncytium

Question 24

What does the ultrastructure include?

Answer 24

-Endocardium(endothelial tissue)
-Myocardium(muscle)
-Epicardium(thin external membrane)

Question 25

What are Atria and ventricles separated by?

Answer 25

-Non conductive fibrous skeleton

Question 26

What does the spiral arrangement of myocytes allow the heart to do?

Answer 26

-Wring blood from ventricular cavities with each contraction

Question 27

a great deal of _____________________ is present in cardiac myocytes

Answer 27

Mitochondria

Question 28

What is a pericardial Sac?

Answer 28

A double walled membrane that holds the heart in position

Question 29

What is the function of pericardial fluid?

Answer 29

Resistance to movement is reduced by pericardial fluid and it is secreted by the membrane