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Flashcards in Cardiology I & II Deck (82)
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1
Q

Components of the cardiovascular system

A
Heart 
Arteries 
Veins 
Capillaries 
Lymphatic vessels
2
Q

Layers of the heart

A

Epicardium
Myocardium
Endocardium

3
Q

Components of Epicardium

A

Mesothelial lining

Connective Tissue Underlying the mesothelium

4
Q

Mesothelial Lining of the epicardium

A

covers the external surface of the heart

5
Q

Connective tissue underlying mesothelium of the epicardium

A

Loose connective tissue, adipose tissue
Nerves pass through this layer
Blood vessels travel to the myocardium through this layer

6
Q

Principle component of heart wall

A

Myocardium (thickest layer)

7
Q

Thickness of myocardium in the atria vs ventricles

A

Thicker in the ventricles

8
Q

Most internal layer of the heart

A

Endocardium

9
Q

Components of endocardium

A

endothelium
subendothelial connective tissue
impulse conducting system

10
Q

Describe the internal skeleton of the heart

A

Four fibrous rings that surround the valve orifeces

All within the atrioventricular plane (one continuous sheet)

11
Q

Purpose of a trigone

A

to connect fibrous tissue rings surrounding valves together

12
Q

left atrioventricular rings surrounds what valve

A

Mitral valve

13
Q

Right atrioventricular ring surrounds what valve

A

Tricuspid

14
Q

Left trigone connects what?

A

left atrioventricular ring (mitral) and aortic fibrous rings

15
Q

Right trigone connects what?

A

left (mitral) and right (tricuspid) atrioventricular rings

16
Q

Membranous Part of the interventricular septum

A

Devoid of cardiac muscle
Composed of dense irregular connective tissue
Contains part of the AV bundle

17
Q

Where dies Ventricular Septal Defect occur

A

in the membranous portion of the IV septum

18
Q

layers of valves

A

1: Fibrosa
2: Spongiosa
3: Atrialis

19
Q

Fibrosa

A

formed of DICT connected to corresponding fibrous ring

Extends form the base along the ventricular side of atrioventricular valves

20
Q

Which layer of the valve faces the ventricular side of the atrioventricular valve

A

fibrosa

21
Q

Spongiosa

A

Formed of loose connective tissue

large amounts of elastic fibers

Most prominent on free edges of the valve

22
Q

Where do you find the spongiosa layer of the valve, what is the purpose of this layer

A

most prominent on the free edges

Purpose: shock absorption (dampens vibrations as the valve closes)

23
Q

Atrialis

A

covers the atrial aspect of spongiosa
Rich in proteoglycans
Contains elastic fibers and occasional smooth muscle cells

24
Q

What layers of the valve contain elastic fibers

A

Spongiosa

Atrialis

25
Q

Which layer(s) of the valve (may) contains some smooth muscle cells?

A

Atrialis

26
Q

Mirtal Valve stenosis

A

inflammation of valve leaflets that promotes angiogenesis leading to formation of fibrotic tissue resulting in stenosis of the valve

Rheumatic fever can be a cause

27
Q

Describe the ANS and heartbeat

A

ANS can REGULATE the heart beat but it does not INITIATE heartbeat

28
Q

Parasympathetic - HR

A

Decrease HR

29
Q

Sympathetic- HR

A

Increases HR

30
Q

Effect of hormones and other substances on HR

A

can change the rate and force of contraction

ex: Epinephrine, thyroid hormones, caffeine

31
Q

What are cardiac conducting cells called

A

Purkinje Fibers

32
Q

Describe Purkinje fibers

A

modified cardiac myocyte (modified to conduct electrical impulses)

contain a lot of glycogen
can transmit faster than myocytes
still have intercalated discs

33
Q

What do Purkinje fibers form

A

Nodes and bundles

including the sinoatrial and atreoventricular node and bindle of His

34
Q

Myocardial infaction

A

caused by obstruction of coronary arteries and loss of blood supply to the cardiac muscle for more than 20 minutes

35
Q

Is MI reversible? Why

A

No- Nuclei get spit out (cell death)

myocytes are unable to regenerate/ proliferate and get replaced by a scar

36
Q

Atherosclerosis involves what layer of the vessel

A

Tunica intima thickening- narrows the lumen eventually causing rupture- clot will form due to exposed collagen

37
Q

Most common benign tumor of the heart

A

Myxoma (bunch of loose connective tissue)

Commonly found in the left atrium

38
Q

Angiosarcoma

A

rare tumor that originates in the heart (1/3 of all tumors that originate in the heart)

39
Q

One of the most common tumors to spread to the heart

A

Metastatic Melanoma

40
Q

Layers of blood vessels

A

Tunica intima
Tunica media
Tunica Adventitia

41
Q

Components of tunica intima

A

endothelium
subendthelial connective tissue
internal elastic lamina

42
Q

What lines the luminal surface

A

Endothelium of the tunica intima

43
Q

Functions of Endothelium

A

1: Selective permeability (transcellular, paracellular, fenestrations)
2: Non-Thrombogenic factor
3: Modulation of blood flow
4: Regulation/Modulation of Immune Responses
5: Hormonal Synthesis
6: Metabolic activity

44
Q

Endothelium

Transcellular pathway

A

allows active transport across the plasma membrane

Clatherin- independent pathway is used to transport material from blood into the cell

Clatherin- DEpenent pathway is used to transport LDL and cholesterol

45
Q

Endothelium

Paracellular Pathway

A

Passive transport across zonula occuludens

Normally blocked by zonula occludens but in the case of inflammation the immune cells need to get out of the blood(causes edema and allows extravagation)

46
Q

Endothelium

Fenestrations

A

Endothelial cells have holes in them that allow for the passage of fairly large molecules

(kidney and endocrine glands)

47
Q

Endothelium

Non-Thrombogenic Barrier

A

Produce/ Secrete

- Anticoagulants (thrombomodulin) 
- Antithrombogenic substances 

In situations when the endothelium becomes damaged it secretes Thrombogenic agensts such as von Willebrand factor (triggers the clotting cascade)

48
Q

Endothelium

Modulation of blood flow

A

Vasoconstrictors

 - ACE (increase BP through Angiotensin) 
 - Endothelian 
 - Thromboxane 

Vasodialators

- NO 
- Prostacyclin
49
Q

Endothelium

Regulation/Modulation of Immune Responses

A

control of leukocyte adhesion (movement of wbc into blood)

Secretion of interleukins and cytokines (IL-1, IL-6, IL-8)

50
Q

Endothelium

Hormonal synthesis

A

Growth factors

  • Colony stimulating factor (CSF)
  • Fibroblast growth factor (FGF)
  • Platelet derived growth factor (PDGF)

Growth factor inhibitors
- Tranforming growth factor B (TGF-B)

51
Q

Endothelium

Metabolic activity

A

Angiotensin I –> Angiotensin II

through ACE to increase blood pressure

52
Q

Subendothelial layer of tunica intima

A

Loose connective tissue

53
Q

Internal Elastic Lamina of tunica intima

A

flattened fenestered sheet of elastin

separates tunica intima from tunica media

54
Q

Tunica Media

A

middle layer of blood vessels

mostly smooth muscle (circularly arranged)

External elastic lamina

55
Q

Where is external elastic lamina located

A

tunica media

56
Q

where is internal elastic lamina located

A

tunica intima

57
Q

What is the purpose of tunica media

A

maintain the architecture of the vessel

58
Q

Tunica Adventitia

A
Most external layer 
composed of mostly connective tissue 
smooth muscle fibers (longitudinally arranged) 
Small blood vessesl (vasa vasorum) 
small nerves (nervi vasorum)
59
Q

Which layer of blood vessels contains longitudinally arranged smooth muscle?

A

Tunica adventitia

60
Q

Which layer of blood vessels contain circularly arranged smooth muscle?

A

Tunica media

61
Q

Which blood vessel layer contains small blood vessels and veins

A

Tunica media

62
Q

Three major types of arteries

A

Large elastic (conducting)
Muscular arteries
Small arteries and arterioles

63
Q

Which type of arteries controls resistance

A

Small arteries and arterioles

64
Q

Purpose of Arterioles

A

control blood flow to capillary network

Contracting smooth muscle cells

Depending on the type of activity the arterioles direct the blood to the organs that need it most

65
Q

Do capillaries contain three tunics in their walls?

A

No- walls are made up of single layer of epithelium and their basal lamina

66
Q

Types of capillaries

A

Continuous Capillaries
Fenestrated Capillaries
Discontinuous Capillaries

67
Q

Continuous Capillaries

A

Continuous basal lamina

tight occluding junctions

68
Q

Where are continuous capillaries found

A

muscles, lungs, CNS

69
Q

Fenestrated capillaries

A

small holes in the endothelial cells (10-100 mm)

** basal lamina remains intact (acts as a filter)

70
Q

Where are fenestrated capillaries found

A

in tissues where there is substantial fluid transport

intestinal villi, choroid plexus, renal glomeruli, endocrine organs

71
Q

Discontinuous capillaries

A

endothelial cells separated by larger gaps (150-175 mm)

** holes extend into the basal lamina

72
Q

Where are discontinuous capillaries found

A

Liver (sinusoids), spleen, bone marrow

73
Q

Three major types of veins

A
Small veins (venules) 
Medium veins (less than 1 cm) 
Large veins (greater than 1 cm)
74
Q

Divisions of small veins

A

Postcapillary venules

Muscular venules

75
Q

Postcapillary venules

A

receive blood from capillaries

76
Q

What layer is missing in postcapillary venules

A

tunic media

77
Q

Principle site of immigration of WBC

A

Postcapillary venules - High endothelial venules

78
Q

High endothelial venules

A

postcapillary venules of lymph organs

have columnar endothelium

79
Q

Muscular Venules

A

collect blood from postcapillary venules

have a tunica media - VERY thin

80
Q

order of venous blood flow

A

1: Post capillary venule
2: Muscular venules
3: Medium veins
4: Large veins
5: Heart

81
Q

purpose of venous and lymphatic valves

A

ensure unidirectional flow

82
Q

Permeability of lymphatic capillaries compared to blood capillaries

A

Greater permeability of lymphatic capillaries