How the CVS fails

Question 1

Stroke

Answer 1

Rapid loss of brain function due to loss of perfusion to parts of the brain

Cerebrovascular accident

Question 2

Haemorrhagic stroke

Answer 2

Cerebral blood vessel rupture

Question 3

Ischaemic stroke

Answer 3

Cerbebral blood vessel blockage

Question 4

Causes of BV burst

Answer 4

Stresses

• high pressure
• large diameter/ high wall tension
• low elasticity/ low compliance
• turbulent flow

Damage

• trauma
• atherosclerosis
• diabetes

Question 5

Vessel wall tension

Answer 5

Tension in a cylinder is the force trying to rip the wall apart
Proportional to P x radius
Larger the vessel, greater the wall tension

Question 6

Compliance

Answer 6

The change in volume caused by a change in pressure

Question 7

Causes of turbulent flow

Answer 7

Junctions
Mixing
Obstacles 
- atherosclerosis
- endothelial damage

Question 8

Endothelium activities (6)

Answer 8

Blood vessel tone: local control of perfusion, vasodilation
Fluid filtration: blood brain barrier, CSF, kidney, GI secretions
Haemostasis: esp fibrinolysis
White cell recruitment: atherosclerosis
Angiogenesis
Hormone trafficking

Question 9

Transcytosis

Answer 9

The transport of molecules across the cytoplasm, especially the epithelium

Question 10

Acute myocardial infacrtion

Answer 10

Region of heart tissue is dead or dying
Usually caused by blocked coronary artery
Reduces the capacity of the heart to pump

Question 11

Atherosclerosis

Answer 11

A disease process resulting in furring of the arteries

Asymptomatic but can lead to other disorders

Question 12

Coronary artery disease

Answer 12

A disease process resulting in obstruction of the arteries supplying heart tissue

Angina or asymptomatic

Primary causes is atherosclerosis

Question 13

Treatment for coronary artery disease

Answer 13

Drugs for hyperlipidaemia, angina or hypertension

Stenting or surgically replacing clogged vessels

Question 14

Plaque rupture

Answer 14

When the fibrous cap of a plaque bursts open

Can cause a thrombus or and embolism

Question 15

MI: sympathetic activity

Answer 15

Sympathetic nervous system releases adrenaline and noradrenaline
- response to pain and haemodynamic abnormalities

In heart failure leads to:

• increased HR
• increased contractility
• increased PR
• increased risk of arrhythmia

Question 16

Forces on H2O in capillaries

Answer 16

Arterial end:

• low osmotic pressure
• high hydrostatic pressure
• net movement into lymphatic system

Venous end

• high osmotic pressure
• low hydrostatic pressure
• net movement into capillaries

Question 17

Pulmonary oedema

Answer 17

Fluid accumulation in lungs so impaired gas exchange as O2 diffusion is lengthened

Caused by left heart failure

Symptoms:

• dyspnoea, orthopnoea
• hypoxia

Question 18

Ascites

Answer 18

Accumulation of fluid in the peritoneal cavity

Many causes including heart failure

Question 19

Peripheral oedema

Answer 19

Swelling of tissues, esp ankles

Many causes, esp chronic low output heart failure

Question 20

Compensation

Answer 20

Maintaining homeostasis of a physiological function despite stresses or malfunctions

Question 21

Decompensated heart failure

Answer 21

Medical emergency
The failure of the heart to maintain adequate blood circulation after long standing vascular disease
Respiratory distress
Kidneys increase plasma volume to compensate for poor perfusion of renal tissue, leads to fluid overload

Question 22

Cardiac remodelling

Answer 22

Growth of cardiac muscle

Caused by injury:

• MI
• hypertension
• valve disease

Results in hypertrophy or dilation

Question 23

Ventricular hypertrophy

Answer 23

Response to work
Athlete’s heart
Eccentric: dilate due too volume overload
Concentric: thicken due to pressure overload

Question 24

Antidiuretic hormone

Answer 24

Also called vasopressin
Causes kidneys to reabsorb more water
Decreases diuresis
From posterior pituitary
Peptide

Question 25

Aldosterone

Answer 25

Causes kidneys to reabsorb more NaCl Directly decreases natriuresis which decreases diuresis From adrenal cortex Steroid

Question 26

Natriuresis

Answer 26

Loss of sodium to the urin

Question 27

Diuresis

Answer 27

Loss of water to the urine

Question 28

Angiotensin II

Answer 28

Increases pressure Vasoconstriction Increased fluid retention - increases aldosterone secretion by adrenal cortex - increases ADH secretion by posterior pituitary Contributes to ventricular hypertrophy and remodelling

Question 29

Angiotensin I

Answer 29

Precursor of angiotensin II | Decapeptide

Question 30

Angiotensin converting enzyme

Answer 30

The enzyme that converts inactive Ang I into vasoactive Ang II Secreted by the kidneys and lungs

Question 31

Renin- angiotensin- aldosterone system

Answer 31

Angiotensinogen converted to Ang I with renin enzyme Ang I converted to Ang II with ACE ACE causes an increase in aldosterone secretion by adrenal cortex

Question 32

Thiazide and thiazide like diuretics

Answer 32

E.g. indapamide Blocks reabsorption at the distal convoluted tube

Question 33

Loop diuretics

Answer 33

E.g. furosemide Blocks reabsorption in the thick loop

Question 34

K+ sparing diuretics

Answer 34

E.g. spironolactone Inhibits aldosterone receptors in cortical collecting duct

Question 35

Chronic low output heart failure

Answer 35

Cardiac output is low, usually due to accumulated damage to the heart Chronic condition with poor 5 year survival rate

Question 36

Left heart failure

Answer 36

Respiratory symptoms Right heart pumps into lungs but left atrium is too full Increased hydrostatic pressure in pulmonary circulation

Question 37

Right heart failure

Answer 37

Systemic symptoms Increased central venous pressure Can lead to peripheral oedema

Question 38

Heart failure symptoms and signs

Answer 38

``` Fatigue especially during exertion Peripheral oedema Dyspnoea - orthopnoea - paroxysmal nocturnal dyspnoea ```

Question 39

Cardiogenic shock

Answer 39

Critically low perfusion due to low cardiac output Medical emergency Progresses by positive feeback

Question 40

Chronic heart failure treatments

Answer 40

ACE inhibitors Diuretics Beta blockers

Question 41

Fluid overload

Answer 41

``` Pathological state where there is too much fluid in the blood Symptoms: - peripheral oedema - ascites - pulmonary dyspnoea - increased central venous pressure ```