Lecture 1: Overview And Anatomy STUDY GUIDE FOR QUIZ

Question 1

1. What are the major functions of the cardiovascular system?

Answer 1

• Transport essential substances to tissues
• Remove by-products of metabolism
• Regulation of body temperature
• Humoral communication throughout body
• Adjustments of oxygen and nutrient supply in different physiologic states

Question 2

2. Why is the heart considered two pumps?

Answer 2

• The RV = pulmonary circulation

- The LV = systemic circulation

Question 3

3. What parts of the heart cause unidirectional flow in the cardiovascular system?

Answer 3

Valves

Question 4

4. What part of the circulation distributes blood to the tissues?

Answer 4

LV = systemic circulation

Question 5

5. What part of the circulation contains the majority of the total blood volume?

Answer 5

-The venules, veins, and vena cava = 70% of total blood volume

Question 6

6. The greatest resistance to blood flow occurs in what part of the circulation?

Answer 6

The arterioles.

Question 7

7. What is the function of the capillaries?

Answer 7

Gas exchange

Question 8

8. Is blood flow pulsatile or non-pulsatile in the capillaries?

Answer 8

Non-pulsatile

Question 9

9. As the cross-sectional area of a vascular bed increases, the velocity of blood flow increases or decreases?

Answer 9

Decreases.

Question 10

10. What contributes to optimal conditions for capillary function?

Answer 10

Blood flow velocity is very slow

Question 11

11. What is the control of blood flow related to in the majority of the tissue beds in the body?

Answer 11

The blood flow to each tissue of the body is almost always precisely controlled in relation to tissue needs

Question 12

1. Describe the boundaries of the mediastinum.

Answer 12

• Superior = above plane between sternal angle and inferior border of T4 vertebral body
• Inferior = anterior, middle, posterior

Question 13

2. In what part of the mediastinum is the heart located?

Answer 13

-In the inferior middle mediastinum

Question 14

3. Name the different layers of the pericardium.

Answer 14

• Fibrous

- Serous–parietal layer, visceral layer

Question 15

4. What nerves travel across the pericardium to the diaphragm? From which nerve roots do these nerves originate?

Answer 15

• Phrenic nerves

- Originate from C3, C4, C5

Question 16

5. What is the sympathetic innervation to the heart?

Answer 16

• T1-T4 = “cardiac accelerators”
• Stellate ganglia (cervicothoracic ganglia) and middle cervical ganglia
• Distributed throughout the heart

Question 17

6. What is the parasympathetic innervation to the heart?

Answer 17

• Originate in the medulla oblongata
• Vagus nerves
• Much innervation to SA and AV nodes
• Little innervation to ventricles

Question 18

7. What are the different parts of the conduction system?

Answer 18

• SA node–interatrial pathway = SA to LA; internodal pathway = SA to AV
• AV node
• Bundle of His (AV bundle)
• Bundle branches–right and left bundle branches (left has left anterior division and left posterior division)
• Purkinje fibers

Question 19

8. What structures are part of the right atrium?

Answer 19

• Vena Cavae
• Crista terminalis
• Coronary sinus
• Fossa ovalis
• Tricuspid valve

Question 20

Vena Cavae

Answer 20

• Superior

- Inferior–Eustachian valve

Question 21

What does the Crista terminalis do?

Answer 21

• Divides the right atrium
• Right atrial appendage (right auricle); trabeculated
• Smooth portion of atrium around vena Cavae

Question 22

9. What is the coronary sinus?

Answer 22

• It is a venous channel that receives blood from the coronary veins and empties into the right atrium of the heart
• Responsible for venous drainage of the heart

Question 23

Fossa ovalis

Answer 23

-Remnant of foramen ovale

Question 24

10. Describe the tricuspid valve apparatus. How many leaflets does the valve have?

Answer 24

-3 leaflets

Question 25

11. The tricuspid valve separates which cardiac chambers?

Answer 25

-The right atrium and right ventricle

Question 26

12. Describe the shape of the right ventricle in cross-section.

Answer 26

• Crescent-shaped
• Coarsely trabeculated inlet
• Smooth outlet (right ventricular outflow tract, RVOT)

Question 27

13. Describe the thickness of the walls of the RV in comparison to those of the LV.

Answer 27

-The right ventricle is thin-walled as compared to LV.

Question 28

14. Which portion of the ventricle is common to both the RV and LV?

Answer 28

The inter ventricular septum

Question 29

15. Describe the shape of the left ventricle in cross-section.

Answer 29

Circular in cross-section.

Question 30

16. How many pulmonary veins are normally present? What cardiac chamber do they drain into?

Answer 30

• 4

- Drain into the left atrium

Question 31

17. Is pulmonary vein blood oxygenated or deoxygenated?

Answer 31

Oxygenated

Question 32

18. In what left atrial structure may blood clots (thrombi) develop in the setting of atrial fibrillation?

Answer 32

Left atrial appendage

Question 33

19. What is the function of the papillary muscles?

Answer 33

To prevent the back flow of blood from the ventricles into the atria during ventricular systole.

Question 34

20. What cardiac valves have associated papillary muscles?

Answer 34

• Tricuspid valve (right)

- Mitral valve (left)

Question 35

21. How many leaflets are found in a normal aortic valve?

Answer 35

-3 (trileaflet)

Question 36

22. Where are the origins of the coronary arteries in relationship to the aortic valve?

Answer 36

-Right and left main coronary arteries originate from the sinuses of valsalva–Dilatations of the ascending aorta that occur just above the aortic valve

Question 37

23. How many leaflets are found in the mitral valve?

Answer 37

-2–anterior (wide and short) and posterior (narrow and long)

Question 38

24. How many leaflets are found in the pulmonic valve?

Answer 38

-3

Question 39

25. Know between which major structures the 4 valves are located–mitral, tricuspid, pulmonic, aortic.

Answer 39

• Tricuspid valve separates the RA/RV
• Mitral valve separates the LA/LV
• Pulmonic valve separates the RV/PA
• Aortic valve separates the LV/aorta

Question 40

26. Know the major branches of the coronary arteries.

Answer 40

Right coronary artery supplies the posterior descending artery (PDA)

Left main coronary artery bifurcates to form:

• Left anterior descending (LAD) (diagonal branches)
• Left circumflex (obtuse marginales)

Question 41

27. What is the ramus intermedius?

Answer 41

-The additional branch in people who have a tri-furcation of the left main coronary artery.

Question 42

28. What determines dominance in regards to the coronary arteries?

Answer 42

The artery that supplies the posterior third of the interventricular septum—the posterior descending artery (PDA)—determines the coronary dominance.

In 85% of people, the right coronary artery supplies the posterior descending artery, so coronary circulation can be classified as “right-dominant.”

Question 43

29. Know the coronary artery blood supply to the various portions of the LV.

Answer 43

Left main coronary artery =

• Left anterior descending artery — diagonal branches
• Left circumflex artery — obtuse marginales branches
• In 37% of people—trifurcation of the left coronary artery = ramus intermedius (third branch of the left coronary artery)