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Anatomy & Physiology > Cardiovascular system > Flashcards

Flashcards in Cardiovascular system Deck (113):
1

What 3 factors regulate Cardiac Stroke Volume

1. The degree of stretch in the heart before it contracts
2.The forcefulness of contraction of individual ventricular muscle fibres
3.The pressure required to eject blood from the ventricles

2

What is the inflammation of the endocardium typically involving the heart valves? [Mostly caused by bacteria]

[Bacterial] Endocarditis

3

What is myocarditis

Inflammation of the myocardium that usually occurs as a complication of a viral infection, rheumatic fever or exposure to radiation or certain chemicals or medications

4

Medical term for Heart Enlargement?

Cardiomegaly

5

What is Cardiac Catheterization

A procedure used to visualise the heart's coronary arteries, chambers, valves and great vessels.

6

What is the medical term meaning cessation of an effective heartbeat

Cardiac Arrest

7

What is the medical term describing failure of the myocardium to contract

Asystole

8

Name the X-ray examination of the heart and great blood vessels after injection of a radiopaque dye into the bloodstream

Angiocardiography

9

List some types of arrythymias

SVT - Supraventricular Tachycardia
Heart Block
APC - Atrial Premature Contraction
AF - Atrial Fibrillation
VPC - Ventricular Premature Contraction
VT/Vtach - Ventricular Tachycardia
VF Ventricular Fibrillation

10

What does arrhythmia or dysrhythmia refer to?

An abnormal rhythm as a result in the conduction system of the heart. The heart may beat too fast or too slow.

11

What does PDA stand for and what is it?

Patent Ductus Arteriosus - A congenital heart defect

12

What are the treatments for myocardial infarction

Injection of a thrombolytic (Clot dissolving) agent e.g. streptokinase or tpa, plus heparin (anti-coagulant)
OR
Performing coronary angioplasty
OR
Coronary artery bypass grafting

13

What might happen if the size and location of an infarcted area of heart tissue is significant?

It may disrupt the conducting system of the heart and cause sudden death by triggering ventricular fibrillation

14

What happens to the heart tissue distal to an obstructed artery?

The tissue dies and is replaced by non-contractile scar tissue and consequently the heart loses some of its strength

15

What does infarction mean?

The death of an area of tissue because of interrupted blood supply

16

What might occur as a result of an obstruction to blood flow in a coronary artery?

Myocardial Infarction

17

Which areas of the body is the pain in angina pectoris referred to (in many instances)?

Neck
Chin
Down the left arm to the elbow

18

What is Angina Pectoris and what condition of the heart does it usually accompany?

It literally means "strangled chest" and is a severe pain. It often accompanies myocardial ischemia

19

What is Myocardial Ischemia

The medical term for a condition of reduced blood flow to the myocardium.

20

What drugs are used to treat coronary artery disease?

Anti-hypertensive drugs
Nitroglycerin
Betablockers
Cholesterol lowering agents
Clot dissolving agents (thrombolytic)

21

How are smooth muscle fibres involved in forming an atherosclerotic plaque?

They form a cap on top of the fatty streak formed by the foamy macrophages and T-cells

22

How is it that despite the formation of atherosclerotic plaques in the arteries, blood can flow through the affected arteries with relative ease sometimes for decades?

Atherosclerotic plaques expand away from the bloodstream rather than into it.

23

What is the difference in LDL and HDL? Which type is better for our health?

LDL - Transports cholesterol from liver to body cells for use in cell membrane repair and production of steroid hormones and bile salts
HDL - Removes excess cholesterol from body cells and transports it to the liver for elimination.

High levels of LDLs are associated with higher risk of CAD.

24

Why are high levels of LDL considered bad for our health?

They are associated with a increased risk of Coronary Artery Disease due to their promotion of atherosclerosis. They are often referred to as bad cholesterol.

25

Name two major lipo proteins

LDL - Low density Lipo proteins
HDL - High density Lipo proteins

26

Describe the structure of a lipo protein including where in the body they are made.

Manufactured by the liver and small intestine.
Spherical particle
Inner core of triglycerides and other lipids
Outer shell of proteins, phospholipids and cholesterol

27

What 3 substances make up an atherosclerotic plaque?

1) Fatty substances
2) Cholesterol
3) Smooth muscle fibres

28

How does Homocysteine possibly increase the likelihood of coronary artery disease?

It's an amino acid that may induce blood vessel damage by promoting platelet aggregation and smooth muscle fibre proliferation

29

How does fibrinogen increase the risk of Coronary Artery Disease?

May help regulate cellular proliferation, vasoconstriction and platelet aggregation.

30

What is a Lipoprotein? (In relation to CAD)

LDL like particle
Binds to endothelial cells, macrophages and blood platelets
May promote proliferation of smooth muscle fibres
Inhibits breakdown of blood clots

31

What are C-reactive proteins?

Produced by Liver and maybe present in the blood in inactive form
Converted to an active form during inflammation
May play a direct role in development of atherosclerosis by promoting the uptake of LDLs by macrophages

32

List the risk factors associated with CAD?

Smoking
High BP
Diabetes
High Cholesterol
Obesity
Sedentary Lifestyle
Family History of CAD

33

What is CAD?

Coronary Artery Disease - The effects of the accumulation of atherosclerotic plaques in coronary arteries that lead to a reduction in blood flow to the myocardium

34

Why does hypertension put a strain on the heart?

It increases aortic pressure meaning the pressure in the Left Ventricle must be higher to overcome this pressure and move blood out into the aorta. Eventually ejection gets harder and stroke volume and cardiac output diminish.

35

List some negative inotropic agents which reduce the heart muscle contractility?

Calcium channel blockers
Some anaesthetics

36

List some positive inotropic agents affecting stroke volume

Neurotransmitters - norepinephrine
Hormones - epinephrine and thyroxine
Drugs - Digoxia

37

What are inotropic agents?

Substances that increase or decrease contractility in cardiac muscles (and consequently increase or decrease stroke volume)

38

What 3 factors affect stroke volume?

PRELOAD (Stretch of ventricle muscle prior to contraction)
CONTRACTILITY (forcefulness of ventricular muscle contraction)
AFTERLOAD (Pressure that must be overcome before ventricles can eject blood)

39

What effect to Calcium ions have on the heart?

A moderate increase in Ca 2+ (extra or intracellur) increases heart rate and contraction force.

40

What affect to elevated levels of sodium and potassium ions have on the heart

Decreased heart rate and contraction force

41

What hormones affect heart rate?

Thyroxine
Epinephrine

42

What is one of the signs of hyperthyroidism?

Tachycardia

43

What can trigger the adrenal medullae to release hormones?

Exercise
Stress
Excitement

44

What effects do norepinephrine and epinephrine have on the heart?

They enhance the heart's pumping effectiveness by increasing both heart rate and contraction force.

45

Which part of the body releases epinephrine and norepinephrine?

Adrenal Medullae

46

What are baroreceptors and where are they located?

Sensory receptors
Provide input to Cardiovascular centre
They are neurons (nerve cells) sensitive to changes in Blood Pressure changes
Located in arch of the aorta and carotid arteries

47

Which nerves release the neurotransmitter acetylcholine and which nervous system do they belong to?

Vagus (x) nerves
Parasympathetic Nervous System

48

Which neurotransmitter decreases heart rate and which node does it affect?

Acetylcholine (ACh)
Sino-atrial Node - SA node

49

Which nerves sends signals to the CV Centre?

Glossopharyngeal (IX) nerves
Vagus (X) nerves

50

Where does the CV centre direct output? (in relation to regulation of the heart)

Increases or decreases frequency of nerve impulses sent out to both sympathetic and parasympathetic branches of the ANS

51

What is Frank Starling Law of the heart?

Within limits, the more the heart is stretched as it fills during diastole, the greater the force of contraction during systole.

52

What stimulates the heart to contract more forcefully? (Tip: hormones & medication)

ANS - Epinephrine/Norepinephrine
Increased Ca2+ levels in interstitial fluid
Digitalis (Medication)

53

What will decrease the force of cardiac contractions? (Tip: hormones etc)

Inhibition of Norepinephrine & epinephrine (sympathetic division of ANS)
Anoxia (Absence of oxygen)
Acidosis (Excess acid in body fluids)
Some Anaesthetics
Increased K+ levels in interstitial fluid

54

What happens to stroke volume if pressure in the pulmonary trunk and aorta is higher than normal?

The semi-lunar valves open later than normal, stroke volume decreases and more blood remains in the ventricles at the end of systole.

55

What are the effects of alcohol, caffeine or cigarettes on the body? i.e. NS, Heart etc

Stimulate sympathetic nervous system
Elevate heart rate and BP
Thereby increase risk of hypertension

56

Where does the CV centre direct output? (In relation to regulation of the heart)

Increases or decreases frequency of nerve impulses sent out to both sympathetic and parasympathetic branches of the ANS

57

From where does the CV Centre in the medulla oblongata receive input?

1. A variety of sensory receptors
2. Higher Brain centers e.g. limbic and cerebral cortex

58

Which region of the brain does Nervous system regulation of the heart originate?

Cardiovascular Centre (CV) of the medulla oblongata

59

What are the common causes of congestive heart failure? (Tip: There are 4!)

Coronary Artery Disease
Long term high blood pressure
Myocardial Infarction
Valve Disorders

60

What leads to peripheral oedema in RSHF?

If the right ventricle fails, first blood backs up in the systemic blood vessels - most notable in swelling in feet and ankles.

61

What leads to pulmonary oedema in LSHF?

If left ventricle fails first, it can't pump out all the blood it receives and blood backs up in the lungs

62

What is Congestive Heart Failure?

Heart is a failing pump.
Blood left in ventricles at end of each cycle causes Positive feedback cycle: Less effective pumping leads to even lower pumping capability
Often one side fails first

63

What is an artery?

A blood vessel carrying blood away from the heart

64

What is Ascites?

An accumulation of fluid in the peritoneal cavity.

65

What is atherosclerosis?

A condition where cholesterol and lipid deposits accumulate on the inner layer of the medium and large blood vessels, leading to a narrowing in these vessels

66

What is an athromatous plaque?

A collection of lipids and cholesterol that accumulates in large and medium sized vessels

67

What are Atria?

The upper chambers of the heart

68

What is the Atrioventricular valve?

A heart valve made up of membranous flaps that allow blood to flow in one direction only; also known as the bicuspid valve

69

What is the Bicuspid Valve?

Also known as the atrioventricular valve. It is a valve in the heart that contains two cusps.

70

What is endocardium?

The endothelial membrane that lines the inner surface of the heart

71

What is the inferior vena cava and where is it in the body?

Large vein that returns de-oxygenated blood from parts of the body below the diaphragm to the right atrium.

72

What is the Mediastinum?

A subdivision of the thoracic cavity

73

What is the Mitral Valve?

The left atrioventricular valve

74

What is the Pericardium?

A double layered sac that encloses the heart

75

What is the pulmonary artery?

The vessel that takes de-oxygenated blood from the right ventricle to the lungs

76

What is the pulmonary vein?

The vessel that returns oxygenated blood from the lungs to the right atrium

77

What is the semilunar valve?

A valve that prevents the backflow of blood to the ventricles after contraction

78

What is the superior vena cava?

The large vein that returns de-oxygenated blood superior to the diaphragm to the right atrium.

79

What is the Tricuspid valve?

The right atrioventricular valve

80

What is tunica externa?

Outer layer of blood vessels

81

What is tunica media?

The middle layer of blood vessels

82

What is tunica interna?

The inner layer of blood vessels

83

What is the structure and function of the tunica externa?

Composed of collagen fibres
Protects and supports blood vessels
Secures blood vessels to surrounding tissues

84

What type of nerve fibres supply the tunica externa?

Sympathetic nerve fibres

85

What type of tissue does the tunica media contain?

Smooth muscle
Elastic tissue

86

What tissue type is the tunica interna made up of?

Endothelia

87

Is the tunica interna smooth or rough?

Smooth

88

Why is the tunica interna smooth?

To prevent friction from the flow of blood

89

What are the 3 groups of arteries?

Elastic
Muscular
Arterioles

90

What are the vasa vasorum?

A network of blood vessels that supply the tunica externa with blood.

91

List characteristics of an Elastic Artery

Contain high proportion of elastic fibres in tunica media
Thick walled
Found near the heart
Large lumen

92

What is another name for Elastic Arteries

Conducting Arteries

93

List characteristics of Muscular Arteries

Medium sized
Contain more smooth muscles
Contain fewer elastic fibres

94

What are Muscular arteries otherwise known as?

Distributing arteries

95

List examples of Muscular arteries

Axillary
Brachial
Radial
Splenic
Femoral
Popliteal
Tibial

96

What is the function of arterioles?

Regulate blood flow to capillaries by altering diameter of capillaries.

97

What tissue are capillaries composed of?

Tunica Intima

98

What is a function of capillaries?

Linking arterioles to venules
Allow water, nutrients, gases and waste products in and out of blood supply

99

Which two sites of the body do not contain capillaries?

Cornea of the eye
Epidermis of the skin

100

What type of specialist cell are found in venules?

Fibroblasts

101

Which has a larger lumen, vein or artery?

Vein

102

What do veins have that arteries do not?

Bicuspid Valves

103

What is Blood Pressure?

The force exerted by the circulating blood on the walls of the blood vessels. It refers to Arterial blood pressure

104

What are the 3 main factors that regulate blood pressure?

Neuronal regulation
Hormonal regulation
Autoregulation of blood pressure

105

Where are the baroreceptors located?

Carotid sinus & Aortic arch

106

Where are the chemoreceptors located?

Aortic and carotid bodies

107

What is the function of the aortic and carotid bodies?

They detect changes in oxygen, carbon dioxide and hydrogen ion concentrations

108

List 5 hormones involved in BP regulation

Renin-angiotensin system
Epinephrine (adrenalin)
Norepinephrine (noradrenaline)
Antidiuretic hormone
Natriuretic peptide

109

List 5 factors that affect BP
(Not age, gender, stress, hormones, drugs

Cardiac Output
Circulating Volume
Peripheral Resistance
Blood viscosity
Hydrostatic pressure

110

What is the Aorta?

First major blood vessel of the arterial circulation. Emerges from the left ventricle of the heart

111

What is a baroreceptor?

A neuron sensing changes in fluid, air and blood pressure

112

What is a chemoreceptor?

A sensory receptor that detects the presence of a specific chemical

113

What is erythema?

A superficial reddening of the skin