Cardiovascular Phsyology Flashcards
1
Q
What’s an intercalated disk
A
The space between two cardiac cells
2
Q
What is a gap junction
A
Channels allow ion flow between cells fro rapid AP conduction
3
Q
What are desmosomes
A
Physical protein connections between cells
4
Q
What is the order of an action potential in the nodes in the heart
A
Slow depolarisation (pacemaker potential) Rapid depolarisation (action potential) Repolorisation
5
Q
What is special about pacemaker cells?
A
They fire spontaneously
6
Q
What is the cardiac contractile cells process
A
Depolarisation (sodium floods in) Repolarisation (calcium ions out) Plateau (k channels shut ca open) Repolorisation (delayed I out of cell) Resting potential
7
Q
What is Einthoven Triangle
A
A triangle of electrodes right are left arm and left leg forming equilateral triangle around the heart
8
Q
What are the ECG leads
A
1 2 and 3 anti-clockwise around the heart
9
Q
What is the p wave?
A
Atrial depolarisation
10
Q
What is theQRS complex
A
Ventricular depolarisation
11
Q
What is the t wave
A
Ventricular repolorisation
12
Q
What is the PQ interval
A
AV node conduction time
13
Q
What is the QT interval
A
Ventricular systole
14
Q
What is the TQ interval
A
Ventricular diastole
15
Q
What is the RR interval
A
Time between heartbeats
16
Q
What is an arrhythmia?
A
Heart beat too fast or too slow
17
Q
What is a third degree block
A
No conduction via AV node causing out of sync atrial and ventricular contractions
18
Q
What is fibrillation
A
Atria or ventricles don’t beat in a rhythm atrial causes weakness ventricular can cause death
19
Q
What is venous return
A
Blood passing through AV node under its own pressure
20
Q
Isovolumetric contraction
A
Ventricles contract but pressure not enough to open semilunar valves. Volume constant
21
Q
What is ventricular ejection
A
Blood exits
22
Q
What is isovolumetric relaxation
A
Ventricles relax but pressure too high for AV valves to open thus all valves are shut
23
Q
What is systole
A
Contraction
24
Q
What is diastole
A
Heart relaxes
25
What is the dicrotic notch in the aortic pressure diagram
This is the shutting of the aortic valve
26
How do you calculate pulse pressure?
PP=Systolic pressure-diastolic pressure
27
How do you calculate mean arterial pressure?
MAP= diastolic pressure + (pulse pressure/3)
28
What is EDV
End diastolic volume
29
What is ESV
End systolic volume
30
How do you calculate stroke volume?
SV = EDV-ESV
31
How do you calculate ejection fraction ratio
EF = SV/EDV
| Volume in one heart beat divided by volume prior to ejection given as a percentage
32
What is the lub sound
AV valves closing
33
What is the dub sound
Semi lunar valves closing
34
What is it that causes the sounds m?
It is not the snapping shut of valves it is the sound of blood rushing through them as the narrow
35
What is coronary artery disease
This is where atherosclerotic plaque have accumulated in the arteries restricting blood flow causing angina
36
How is coronary artery disease detected
Use and angiography to see thinning arteries radio opaque dye Injected
37
What is an angioplasty
This is where A stent is inserted
38
What is a bglass graft?
This is where open heart surgerey grafts vessels to bypass the blockage
39
What is acyanotic mean?
Blood has normal levels of oxygen
40
What does cyanostic mean
Blood has reduced oxygen hence it’s darker colour
41
What does a septal defect do
Blood flow left too right
42
What happens when the aorta are coarctation
It’s narrowed hence higher blood pressure
43
What is patent duct is arteriosus
This is where a vessel co etc sort and pulmonary trunk
44
What is tetralogy of fallot
4 defects septal defect and right aorta defect causes blue baby
45
How do you calculate cardiac output
CO = heart rate x stroke volume
46
What is extrinsic and intrinsic control of the heart
Intrinsic controlled by factors in the heart extrinsic eg hormonal control outside the heart
47
What are the two parts to the autonomic nervous system
Sympathetic and parasympathetic
48
What is the 1. Parasympathetic neurotransmitter
| 2. Sympathetic neurotransmitter
1 acetylcholine
| 2 noradrenaline
49
What does sympathetic control of the heart do
Increased cardiac output
50
What does parasympathetic control of the heart do
Decreased cardiac output
51
How do hormones control the heart
Adrenaline causes SA node to fire faster
52
What factors effect stroke volume?
Ventricular contractility
End diastolic volume change
Afterload in stroke volume
53
How is ventricular contractility changed
Sympathetic neurones cause greater Ca ion concentration causing increase in contractility
54
What is starlings law of the heart
This is the idea that muscle fibres stretch increasing the contractile force when the stroke volume of the heart increases in response to the volume of blood in the ventricles
55
What circuit are things in the body arranged in
Parallel
56
Where does blood flow the slowest
Capillaries
57
What are the 3 blood vessel layers
Endothelium, smooth muscle, connective tissue
58
What do the different amounts of muscle in arteries mean
Some have more and vaisoconstrict more
59
What is special about arterioles
Control amount of blood to capillary beds
60
Capillary layers?
Endothelium and basement membrane
61
What are fenestration’s
Pores in types of capillaries
62
What are special about fenestrated capillaries
Greater exchange of fluids
63
What is microcirculation
Blood flow through the capillaries
64
What is a precapilary sphincter
Ring of muscle that vaisoconstricts the capillaries
65
What don’t venuoles have
No smooth muscle
66
What do veins have?
Valves
67
How is blood pressure measured
Increase cuff and let down untill blood flow can be heard again
68
Why must capillary blood pressure be closely controlled
Pressure relates to solute control
69
What is the respiratory pump
This is where you inhale and compress the veins forcing blood towards the heart
70
What is the skeletal muscle pump
Skeletal muscles again compress veins and push blood towards the heart
71
How do you calculate MAP
MAP = CO x total peripheral resistance
72
How do you calculate cardiac output
Co= heart rate x stroke volume
73
What is Darcys law?
Flow is proportional to the pressure difference between two points
Flow bing volume in a give time
74
What is laminar flow
Occurs in normal arteries and veins
75
Turbulent flow?
This occurs in the ventricles and ascending aorta
76
Single file flow?
Occurs in capillaries
77
What is flow proportional too
Tube length
| Fluid viscosity
78
What happens if series units are added
Resistance increases
79
What happens if parallel units are added
Resistance decreases
80
What is compliance
Compliance = volume / pressure inside - pressure outside
81
What has a higher compliance
Veins they are thin walled and stretchy
82
Why are forces needed in the blood vessel walls
Tension is needed to withstand translational pressure created by the heart
83
What is the law of Laplace
Tension = (transluminal pressure x radius) / wall thickness
84
Where is vessel rupture most likely
Aorta
85
What is metabolic control of blood flow?
This is where there is a clear correlation between metabolism and blood flow
86
What factors can cause vaisodilation.
Nutrient content
87
What does nitric oxide do
This causes the smooth muscle to relax
88
How is constant blood flow controlled?
Increase and decrease in resistance
89
What is a long term auto regulation?
This is where capillary number and size increase or meet deman. This occurs in the heart due to a partial obstruction of the coronary vessels
90
Does the capillary flavour fluid absorption true or false?
True
91
What is the net fluid balance movement in a capillary bed?
Out at arteries in at venous end
92
What is the main purpose of the lymphatic system
Return lost tisssue fluid and kill pathogens
93
What is the lymphatic system a major transporter of
Fats into the blood via chylomicrons
94
What are lymph nodes
These are clusters of lymphocytes and macrophages
95
What are baroreceptors
These are receptors that detect pressure due to the stretch sensitivity
They are in the aortic arch
96
What happens when baroreceptors are stimulated
The heart rate is decreased
97
What part of the brain controls heart rate
The medulla (cardiovascular centre)
98
What is the baroreceptors reflex an example of.
Homeostasis
99
What happens when someone’s posture changes, laying to standing
Higher pressure to get blood to head
100
What is orthostasis
A sever challenge to CV system and can cause syncope. This happens when standing as EDV volume Lowe so strike volume low and not enough blood moves
101
What is cerebral perfusion pressure
This is the pressure gradient causing blood flow to the brain
102
What happens without baroreceptors
Blood pressure much less stable
103
What are the purpose of atrial receptors
Regulation of blood volume
104
What happens when blood pressure drops?
Stimulation of receptors cause ADH release to increase blood volume
105
What else does ADH do
It causes vaisoconstriction
106
What does denervation mean?
Loss of nerve supply to an area
107
How do chemoreceptors control blood pressure
If O2 CO2 or H+ cha he’s then so does blood pressure
108
What do chemoreceptors do to the lungs
Cause deeper breathing if needed
109
What is the Cushing reaction
Increase in blood pressure and decrease in heart rate and irregular breathing. This is caused by high pressure in the skull or insufficient blood flow. This causes death fast
110
How is blood volume controlled
Kidneys
111
What is the renin-angiotensin-aldetosterone system?
This is caused by blood volume fall
It’s detected by juxtoglomelular class in kidney
Causes vaisoconstriction tasing TPR
Increases NA absorption causing increasing water reavsorbed thus rise in blood volume and CO
112
What is TPR
Total periphrial resistance
113
What does noradrenaline do to the heart
Increases heart rate
114
What does acetylcholine do to the heart
Decreases heart rate
115
What does atrial natiuretic peptide do
Causes water loss at kidneys
116
What does nitric oxide do
Vaisodilation
117
What is the adrenal medulla, what does it secrete
Adrenaline and noradrenaline
118
What receptors do noradrenaline and adrenaline effect
A1 A2 B1 B2 and B3
119
Adrenaline stimulate glycogenolysis what is this?
Break down of glycogen to release glucose
120
What is released when there is familiar stress
Noradrenaline
121
What is released for u familiar stress
Adrenaline
122
What is pharchromocytoma?
This is a tumour on the adrenal medulla it causes high BP and sweating + high blood glucose
123
What is cortisol
This is a hormone released in response to stress and causes motabalism and repair
124
When is cortisol released
When exposed to day light
125
What is Cushing disease?
This is a tumour if adrenal vortex causing cortisol secretion resulting in moon face and buffalo hump
126
What is Addison’s disease?
Low blood pressure susceptibility to stress
127
What is syncope
Fainting due to reduced perfusion pressure to the brain
