Aula 5 - Vascular Disorders Flashcards
1
Q
Complete the sentence:
The vascular system is also known as ________________ system.
A
circulatory
2
Q
Question:
What does the vascular system include?
A
Blood vessels and Lymph vessels
3
Q
Question:
Distinguish the blood from the lymph in terms of constitution.
A
The blood is made of 55% plasma (which is 90% water and 10% proteins, electrolytes, carbohydrates, minerals, etc.) and 45% formed elements (almost 100% red blood cells and around 2% of platelets and white blood cells).
The lymph is made of 96% water and 4% solid parts (which mainly include immune cells, but also proteins, amino acids, lipidic elements, etc.).
4
Q
Question:
What is the main function of blood?
A
Deliver oxygen and nutrients to the organs and recover metabolic residues.
5
Q
Question:
What is the main function of lymph?
A
Transport immune cells and drain interstitial fluids accumulated in excess in tissues.
6
Q
True or False:
The lymph and the blood circulate in a closed loop system, with a central pump.
A
False.
The blood circulates in a closed system, with the heart as a central pump, but lymph circulates in an open system without a main pump.
7
Q
Question:
Distinguish blood and lymph in terms of color.
A
Blood is a reddish fluid, while lymph is a clear colorless or yellowish fluid.
8
Q
Question:
What are the two main types of blood vessels?
A
Venous vessels and Arterial vessels
9
Q
Choose the correct option:
Regarding blood volume distribution:
a) The blood volume is equally distributed between venous and arterial vessels.
b) The majority of blood volume is within arterial vessels.
c) The majority of blood volume is within venous vessels.
A
c)
Venous vessels have 64% of blood, while arterial vessels have ~15%.
10
Q
Question:
Distinguish venous and arterial vessels in terms of function.
A
Venous vessels transport deoxygenated blood, while arterial vessels transport oxygenated blood.
11
Q
True or False:
Venous vessels and arterial vessels are equally distributed in the body.
A
True.
12
Q
Question:
Name the three types of arterial vessels.
A
- Arteries
- Arterioles
- Capillaries
13
Q
Question:
Name the three types of venous vessels.
A
- Veins
- Venules
- Capillaries
14
Q
Question:
What are the four layers of blood vessels?
A
- Lumen: interior of the vessels, where the blood flows.
- Tunica intima: inner layer of endothelial cells.
- Tunica media: intermediate layer of smooth muscle.
- Tunica adventitia/externa: outer layer of connective tissue.
15
Q
Match each number with the respective letter:
1) Tunica intima
2) Tunica media
3) Tunica adventitia/externa
a) Connective tissue
b) Endothelial cells
c) Smooth muscle
A
1) b
2) c
3) a
16
Q
Question:
Distinguish arterial vessels and venous vessels in terms of lumen diameter and wall thickness.
A
Arterial vessels have a smaller lumen (shorter diameter) than venous vessels.
Arterial vessels have thicker walls than venous vessels.
17
Q
Complete the setence:
In ____________ (arterial/venous), typically the tunica adventitia is thicker than the tunica media.
A
venous
18
Q
Question:
What is the thicker layer of arterial vessels?
A
Tunica media
19
Q
True or False:
Both arterial and venous vessels present vasa vasorum and nervi vasorum in tunica adventitia.
A
True.
20
Q
Question:
Distinguish the tunica intima of arterial and venous vessels.
A
Tunica intima of arterial vessels is rough or wavy, while in venous vessels it is smooth.
21
Q
Question:
What are vasa vasorum and nervi vasorum?
A
Vasa vasorum are small blood vessels that self-irrigate blood vessels.
Nervi vasorum are nerves present in blood vessels that control their contraction and dilation.
22
Q
Question:
Why do venous vessels present valver?
A
To prevent blood regurgitation.
23
Q
Complete the sentence:
Larger arterial vessels present ________ (less/more) elasticity.
A
more
24
Q
Question:
Distinguish larger arterial and venous vessels in terms of elasticity.
A
Arterial vessels are more elastic than venous vessels. Therefore, tunica intima and tunica media of arterial vessels present elastic membranes, and these are absent in venous vessels.
25
# **Question:**
What do larger arterial vessels present in tunica intima and tunica media?
Larger arterial vessels present an internal elastic membrane in tunica intima and an external elastic membrane in tunica media.
26
# **Complete the sentence:**
Veins are considered ____________ vessels, for retaining a great portion of blood volume.
capacitance
27
# **Question:**
What is the main function of capillaries?
Supplying blood to tissues by perfusion.
28
# **Question:**
What distinguishes different types of capillaries?
Size and type of fenestrations.
29
# **Question:**
What is the wall of capillaries made of?
Capillaries wall is constituted by an endothelial layer surrounded by a basement membrane (thin, pliable sheet-like type of extracellular matrix).
30
# **Question:**
What are the three types of capillaries?
1. Continuous capillaries
2. Fenestrated capillaries
3. Sinusoidal capillaries
31
# **Question:**
What type of fenestrations do continuous capillaries present?
They have a complete endothelial lining with **tight junctions** between endothelial cells, which are only permeable to small molecules.
32
# **Question:**
What type of fenestrations do fenestrated capillaries present?
They present **pores/fenestrations** in the endothelial lining, besides the tight junctions, making them permeable to larger molecules.
33
# **Question:**
What type of fenestrations do sinusoidal capillaries present?
They have extensive intracellular gaps and incomplete basement membranes, in addition to intercellullar clefts and fenestrations.
34
# **Question:**
What are is the most common type of capillaries? And the least common?
The most common type of capillaries is continuous capillaries and the least common type is sinusoidal capillaries.
35
# **Question:**
Where are fenestrated capillaries found in the body?
Kidneys and small intestine
36
# **Question:**
Where are sinusoidal capillaries found in the body?
Liver, spleen, bone marrow and lymph nodes.
37
# **Question:**
What is the particularity of sinusoidal capillaries, since they have more fenestrations?
Blood flow is very low, allowing for more time for exchanges of substances.
38
# **Question:**
Why do capillaries allow substances exchange?
Because they present fenestrations and are leaky.
39
# **Question:**
Lymphatic vessels are interlaced among blood capillaries, except in...
Central nervous system, bone marow, bones, teeth and cornea.
40
# **Question:**
What are lymphatic vessels made of?
Lymphatic vessels present an endothelial linen in the inner part and present three coats, similarly to blood vessels (including contractile walls of smooth muscle).
41
# **Question:**
Do lymphatic vessels have valves?
Yes, they have semilunar valves to prevent backflow of lymph.
42
# **Question:**
What is the importance of controlling interstitial fluid levels?
To maintain the normal blood and lymph volumes.
43
# **Complete the sentence:**
The interstitial fluid enters ____________ vessels through loose junctions. Then, it drains to ____________ vessels and, in case of excess of fluid, it drains to the right and left ____________________.
capillary lymphatic, lymphatic, subclavian veins
44
# **Complete the sentence:**
Vessels conducting the fluid to a lymph node are called ________ vessels, whereas vessels conducting the fluid away from the lymph nodes are called ________ vessels.
afferent, efferent
45
# **Question:**
Describe a laminar flow.
A laminar flow is the typical blood flow, where there is a growing flow as there is a proximity to the center of the vessel (such that the blood nearest to the walls does not move). This type of flow is smooth and almost silent.
46
# **Question:**
When is blood flow turbulent?
Blood flow may become turbulent due to:
* Contraction of the heart valves, which accelerate the flow.
* Obstruction of blood vessels.
47
# **Complete the sentence:**
Turbulent blood flow emits a turbulent noise, which can be a ________ (murmur/bruit) when heard over blood vessels or a ________ (murmur/bruit) when heard over the heart.
bruit, murmur
## Footnote
Bruit is the sound heard in arterial obstruction.
48
# **Complete the sentence:**
The flow of the blood between the two ends of the circulatory system depend on the ________ difference generated by the heart (as the pump) and on the ____________ to the flow offered by the blood vessels.
pressure, resistance
49
# **Question:**
How does the viscosity of blood affect the velocity of blood flow?
Higher viscosity, lower velocity.
50
# **Question:**
How does the radius of the vessel affect velocity, resistance and pressure?
⬇ radius
⬇ velocity of blood flow
⬆ resistance
⬆ pressure
51
# **Complete the sentence:**
Arterial pressure is typically measured around the upper arm at the heart level with a ________. It relies on an auscultatory methods based on the sounds of ________.
sphygmomanometer, Korotkoff
52
# **Question:**
What controls the resistance of the vessels?
Hormones (e.g., vasopressin, angiotensin II, epinephrin) and neural system.
53
# **Complete the sentence:**
Arterial pressure is detected by ________________ and controlled by ________________ and ________________.
baroreceptors, baroreflex, reninangiotensin-aldosterone (RAA) system
54
# **Question:**
Write the mathematical formula of mean arterial pressure.
Mean arterial pressure = cardiac output x resistance of the vessels
55
# **Complete the sentence:**
Cardiac output is affected by ________ and ____________.
heart rate, stroke volume
56
# **Question:**
Why do men have higher blood pressure?
Estrogen reduces arterial pressure and men have less estrogen than women.
57
# **Complete the sentence:**
The higher the blood pressure, the ________ (lower/higher) the risk.
higher
## Footnote
Risk of hypertension and hypertensive crisis.
58
# **Complete the sentence:**
Cardiovascular adjustments are achieved by changes in the ____________________ and in ________________________.
cardiac output, blood vessels diameter
59
# **Question:**
What are the five main actions to control blood vessels diameter?
1. Action of vasodilator metabolites
2. Autoregulation
3. Action of vasoregulatory substances produced by endothelial cells
4. Action of circulating vasoactive hormones
5. Action of vasomotor nerves
60
# **Question:**
What is the role of vasodilator metabolites?
Active tissues produce metabolic byproducts that influence blood vessel dilation to increase blood supply.
61
# **Question:**
What are the main vasodilator metabolites?
CO₂ (carbon dioxide) and K⁺ (potassium)
62
# **Question:**
How do vasodilator metabolites work in the case of hypercarnia (high levels of CO₂)?
**Pathway of Vasodilation:**
1. **Increased CO₂ (Hypercapnia)** → More CO₂ leads to an increase in H⁺ (protons).
2. **Increased H⁺** → Lowers pH (acidifies the environment).
3. **Activation of K⁺ channels** → Allows potassium to flow out of endothelial cells.
4. **Hyperpolarization of endothelial cells** → Reduces intracellular calcium (Ca²⁺).
5. **Reduced intracellular calcium** → Leads to **vascular relaxation and vasodilation**.
63
# **Question:**
How does increased CO₂ lead to vasodilation?
Increased CO₂ increases H⁺ levels, lowering pH, which activates K⁺ channels (K⁺ leaves the cells), leading to hyperpolarization of endothelial cells and reduced intracellular calcium, causing vasodilation.
64
# **Question:**
What is the role of K⁺ in vasodilation?
Sodium-potassium channels open, allowing K⁺ to leave the cell and causing hyperpolarization of endothelial cells, which reduces intracellular calcium and leads to vascular relaxation and dilation.
65
# **Question:**
Why does lowering intracellular calcium cause vasodilation?
Calcium is essential for muscle contraction; reducing calcium relaxes the vascular smooth muscle, leading to dilation.
66
# **Question:**
What happens when endothelial cells become hyperpolarized?
It reduces intracellular calcium, which results in vascular relaxation and increased blood flow.
67
# **Question:**
What is autoregulation in the cardiovascular system?
The ability of tissues to maintain a relatively constant blood flow during changes in perfusion pressure.
68
# **Question:**
What is the importance of vasodilation in case of hypercapnia?
Hypercapnia corresponds to increased CO₂ levels. The goal is to remove CO₂ and increase O₂ levels. Therefore, vasodilation will help to increase gases exchange.
69
# **Question:**
What triggers the autoregulation response in blood vessels?
An increase in pressure inside the vessels.
70
# **Question:**
How do smooth muscles in blood vessels respond to increased pressure?
Increased pressure inside the vessels causes smooth muscle stretching, leading to smooth muscle contraction to regulate blood flow.
71
# **Question:**
What is the main function of smooth muscle contraction in autoregulation?
To counteract excessive blood flow by reducing vessel diameter, maintaining stable tissue perfusion.
72
# **Question:**
Why is autoregulation important for organs like the brain and kidneys?
These organs require a stable blood supply to function properly, regardless of fluctuations in blood pressure.
73
# **Question:**
What are the two main substances secreted by the endothelium that regulate blood vessel function?
**Prostacyclin** (promotes vasodilation) and **Thromboxane A₂** (promotes clot formation and vasoconstriction).
74
# **Question:**
What is the precursor molecule for both prostacyclin and thromboxane A₂?
Arachidonic acid.
75
# **Question:**
Which enzyme is involved in converting arachidonic acid into prostacyclin and thromboxane A₂?
Cyclooxygenase (COX).
76
# **Question:**
Where is prostacyclin primarily produced, and what is its main function?
Produced by endothelial cells, it promotes vasodilation and inhibits platelet aggregation.
77
# **Question:**
Where is thromboxane A₂ primarily produced, and what is its main function?
Produced by platelets, it promotes clot formation (platelet aggregation) and vasoconstriction.
78
# **Question:**
Why is a balance between prostacyclin and thromboxane A₂ important?
To ensure clots form when necessary (e.g., injury) while preventing excessive clotting that could block blood flow.
79
# **Complete the sentence:**
Prostacyclin is produced by ________________ (platelets/endothelial cells) and promotes ________________ (vasodilation/vasoconstriction).
endothelial cells, vasodilation
80
# **Complete the sentence:**
Thromboxane A₂ is produced by ________________ (platelets/endothelial cells) and promotes ________________ (vasodilation/vasoconstriction).
platelets, vasoconstriction
81
# **Question:**
How does aspirin affect the production of prostacyclin and thromboxane A₂?
Aspirin **irreversibly inhibits cyclooxygenase (COX)**, reducing the production of both prostacyclin (vasodilation, anti-clot) and thromboxane A₂ (vasoconstriction, pro-clot).
82
# **Question:**
Why does aspirin have a stronger effect on thromboxane A₂ than prostacyclin?
Platelets lack a nucleus and cannot synthesize new COX enzymes, so thromboxane A₂ production remains inhibited for the lifespan of the platelet (**days**). In contrast, endothelial cells can regenerate COX within **hours**, allowing prostacyclin levels to recover faster.
83
# **Question:**
Why is aspirin commonly used as a blood thinner and to reduce formation of thrombus?
By inhibiting thromboxane A₂, aspirin reduces platelet aggregation and clot formation.
84
# **Question:**
What enzyme catalyzes the production of nitric oxide (NO) from arginine?
Endothelial nitric oxide synthase (NOS3)
85
# **Question:**
What is the function of nitric oxide (NO) in the cardiovascular system?
NO is a vasodilator that relaxes vascular smooth muscle, reducing blood pressure and increasing blood flow.
86
# **Question:**
How is nitric oxide (NO) produced in endothelial cells?
NO is synthesized from arginine by nitric oxide synthase (NOS3), activated by intracellular Ca²⁺.
87
# **Question:**
What is the role of cyclic guanosine monophosphate (cGMP) in vasodilation?
NO activates soluble guanylyl cyclase, increasing cGMP, which promotes vascular smooth muscle relaxation.
88
# **Question:**
What happens if NO production is reduced?
Reduced NO leads to less vasodilation, causing higher blood pressure and increased vascular resistance.
89
# **Question:**
Why does administering certain arginine analogs increase blood pressure?
Some analogs of arginine inhibit NOS activity, reducing NO production and leading to vasoconstriction and increased blood pressure.
90
# **Question:**
What intracellular ion activates NOS3 in endothelial cells?
Calcium (Ca²⁺)
91
# **Question:**
How does NO induce vasodilation?
| NO = Nitric Oxide
NO diffuses into smooth muscle cells → Activates soluble guanylyl cyclase → Increases cyclic GMP (cGMP) → Relaxes vascular smooth muscle → Vasodilation
92
# **Question:**
What happens to blood pressure when NO production is increased?
Blood pressure decreases due to vasodilation.
93
# **Complete the sentence:**
When activated, the cGMP cascade leads to ____________ (vasoconstriction/vasodilation).
vasodilation
94
# **Question:**
What are endothelins, and where are they found?
Endothelins are polypeptides found in several cells, including vascular endothelial cells and smooth muscle cells.
95
# **Question:**
How many types of endothelins are there, and which two are found in vascular endothelial and smooth muscle cells?
There are three types of endothelins (ET-1, ET-2, ET-3), but ET-1 (the most abundant) and ET-3 are found in vascular endothelial and smooth muscle cells.
96
# **Question:**
Distinguish endothelin A (ETA) and endothelin B (ETB) receptors in terms of affinity to endothelins.
* ETA receptor has a **great affinity for ET-1**.
* ETB receptor has **equal affinity for all** endothelins (ET-1, ET-3).
97
# **Question:**
Where are endothelin receptors located in the cardiovascular system?
* **Vascular smooth muscle cells** (have both ETA and ETB receptors).
* **Vascular endothelial cells** (have only ETB receptors).
98
# **Question:**
What happens when endothelin receptors on vascular smooth muscle cells are activated?
When endothelin receptors on vascular smooth muscle cells are activated, they lead to **vasoconstriction**.
99
# **Question:**
What type of endothelin receptors are in vascular smooth muscle?
Endothelin A (affinity for ET-1) and Endothelin B (affinity for ET-1 and ET-3) receptors.
100
# **Question:**
What type of endothelin receptors are in vascular endothelial cells?
Only endothelin B receptors (equal affinity for ET-1 and ET-3).
101
# **Question:**
What happens when endothelin B receptors on endothelial cells are activated?
When endothelin B receptors on endothelial cells are activated, they lead to the production of nitric oxide (NO) via nitric oxide synthase (NOS), which activates the cGMP cascade and leads to NO-dependent smooth muscle relaxation and, finally, **vasodilation**.
102
# **Question:**
Why do endothelin receptor activation lead to vasoconstriction in smooth muscle cells and vasodilation in endothelial cells?
Although ETB receptors are present on both cell types, their effects are quite different:
* In smooth muscle, activation of ETA and ETB receptors leads to vasoconstriction due to the increase in intracellular calcium.
* In endothelial cells, activation of ETB receptors leads to the production of NO, which causes vasodilation in the surrounding smooth muscle cells.
103
# **Question:**
Name four vasoconstrictor circulatory hormones.
* Norepinephrine
* Epinephrine
* Vasopressin
* Angiotensin II
104
# **Question:**
Name five vasodilation circulatory hormones.
* Vasoactive intestinal peptide (VIP)
* Kinins
* Atrial natriuretic peptide (ANP)
* Brain natriuretic peptide (BNP)
* C-type natriuretic peptide (CNP)
105
# **Question:**
What are natriuretic peptides, and what role do they play in the cardiovascular system?
Natriuretic peptides (ANP, BNP, CNP) regulate blood pressure, fluid balance, and vascular tone by promoting diuresis and vasodilation.
106
# **Question:**
Which receptors do natriuretic peptides bind to, and what is the outcome of this binding?
Natriuretic peptides bind to NPR-A and NPR-B receptors, which are guanylyl cyclase enzymes that catalyze the conversion of GTP into cyclic GMP (cGMP).
107
# **Question:**
What is the function of cGMP in the body?
cGMP is a second messenger that causes vasodilation, promotes diuresis and natriuresis (increased sodium and water excretion in the kidneys, respectively), and reduces aldosterone secretion.
108
# **Question:**
What is the effect of natriuretic peptides on vascular smooth muscle?
Natriuretic peptides trigger the production of cGMP, which increases the **relaxation** of smooth muscle and leads to vasodilation.
109
# **Complete the sentence:**
Natriuretic peptides (ANP, BNP, CNP) activate the ________ cascade, leading to ____________ (vasodilation/vasoconstriction).
cGMP, vasodilation
110
# **Question:**
What is the role of baroreceptors in regulating blood pressure?
Baroreceptors detect changes in blood pressure. When blood pressure decreases, they initiate neural responses to restore blood pressure to normal levels.
111
# **Question:**
What happens when baroreceptors detect a decrease in blood pressure?
When baroreceptors detect a **decrease** in blood pressure, they stimulate the release of **vasopressin** (also known as antidiuretic hormone, ADH).
112
# **Question:**
How does vasopressin help restore blood pressure after a decrease?
Vasopressin is a vasoconstrictor hormone that **increases contractility of the heart** and promotes **vasoconstriction**, both of which help to increase blood pressure.
Vasopressin also **increases water reabsorption** in the kidneys and **decreases NaCl excretion**, which helps to increase blood volume and raise blood pressure.
113
# **Question:**
What is the overall effect of baroreceptor activation when blood pressure is low?
Baroreceptor activation leads to vasopressin release, which increases water reabsorption, decreases NaCl excretion, increases heart contractility, and induces vasoconstriction, all contributing to an increase in blood pressure.
114
# **Question:**
What are varicose veins?
Twisted, bulging and enlarged veins.
115
# **Question:**
Where do varicose veins most often occur and why?
Legs, due to increased pressure (from blood accumulation) in the veins of the lower body from standing and walking.
116
# **Question:**
List six common causes of varicose veins.
1. Genetic susceptibility
2. Long periods of standing
3. Long periods of sitting
4. Pregnancy
5. Age
6. Obesity
117
# **Question:**
List common symptoms of varicose veins.
* Pain, heaviness or discomfort
* Leg cramps and swelling of the legs
* Itching and sores around the ankles or legs
* Burning sensation
* Changes in the skin, like change in skin color (blue-ish tone) or thickening of the skin
118
# **Question:**
What are the main 2 imaging techniques used to diagnose varicose veins?
Ultrasound and Venogram (X-ray test that shows blood flow in veins)
119
# **Question:**
What are the three main treatment options for varicose veins?
1. Lifestyle changes
2. Compression (socks)
3. Surgery
120
# **Question:**
What lifestyle changes and habits can a patient adopt to effectively manage and alleviate the symptoms of varicose veins?
* Avoid prolonged standing or sitting
* Lose weight
* Exercise to improve circulation
* Use compression socks
121
# **Question:**
What is vasculitis?
Inflammation of the blood vessels.
122
# **Question:**
What are the main complications of vasculitis?
Vasculitis can impair organ perfusion, which can cause ischemia (reduced blood flow), necrosis (tissue death), and inflammation of various organs, depending on the affected blood vessels.
123
# **Question:**
What are the potential causes of vasculitis?
Vasculitis can be a primary disorder or secondary to other causes, and it can be either autoimmune or non-autoimmune.
124
# **Question:**
What clinical manifestations can vasculitis present?
Vasculitis can present with systemic symptoms (affecting the whole body) or organ-specific symptoms (affecting particular organs).
125
# **Question:**
What is the initial cause of the thickening and stiffening of arterial walls in atherosclerosis?
The thickening and stiffening of arterial walls in atherosclerosis is caused by the accumulation of lipids, fibrous elements, and calcifications.
126
# **Question:**
How do alterations in the endothelium contribute to atherosclerosis?
Alterations in the endothelium allow the infiltration of low-density lipoproteins (LDL) into the subendothelial region, which is a key step in atherosclerosis.
127
# **Question:**
What happens to LDL after it infiltrates the subendothelial region in atherosclerosis?
LDL can be oxidized, and the oxidized LDL is recognized by scavenger receptors on macrophages, triggering a cascade of events.
128
# **Question:**
What is the role of macrophages in the development of atherosclerosis?
Oxidized LDL induces the recruitment of monocytes, which differentiate into macrophages, **leading to the formation of foam cells. These foam cells contribute to fatty streaks and plaque formation**.
129
# **Question:**
What is the effect of cholesterol accumulation in macrophages during atherosclerosis?
**Cholesterol accumulation in macrophages can be lipotoxic**, damaging the endoplasmic reticulum and triggering macrophage apoptosis and plaque necrosis.
130
# **Question:**
How does cholesterol accumulation contribute to atherosclerotic plaque formation?
Cholesterol accumulation promotes the formation of cholesterol crystals, which contribute to the development of atherosclerotic plaques.
131
# **Question:**
What is the role of the fibrous cap in stabilizing an atherosclerotic plaque?
The fibrous cap forms over the necrotic core of the plaque, helping to stabilize the plaque and prevent rupture.
132
# **Question:**
Regarding atherosclerosis, what happens to macrophages within the plaque over time?
Accumulated macrophages continue to die and remain retained within the plaque, leading to an increase in the necrotic core.
133
# **Question:**
How does plaque calcification occur in atherosclerosis?
The death of macrophages and vascular smooth muscle cells leads to the calcification of the plaque.
134
# **Question:**
What are the possible outcomes of an atherosclerotic plaque?
An atherosclerotic plaque can cause vessel occlusion or, more commonly, plaque rupture, which triggers thrombosis and blocks blood flow.
135
# **Question:**
What does oxidized LDH do?
Oxidized LDH will stimulate the release of
proinflammatory cytokines that will activate
macrophages and stimulate vascular smooth
muscle cells to produce collagen.
136
# **Question:**
Name some of the risk factors of Atherosclerosis.
* Male gender (low estrogen)
* Family history of ischemic heart disease or stroke
* Hypertension
* Diabetes Mellitus type 1 and 2
* Hyperlipedemia (e.g. high colesterol)
* Obesity
* Smoking (carbon monoxide induces ischemia which enhances formation of plaques)
(etc.)
137
# **Question:**
What are the two main clinical manifestations of atherosclerosis **at the heart**?
Angina pectori (myocardium accumulate “pain-producing” substances) and myocardial infarction (complete occlusion or clotting of coronary arteries).
138
# **Question:**
What is the main clinical manifestation of atherosclerosis **at the brain**?
If there is a complete occlusion or clotting of a brain artery it can lead to **thrombotic strokes.**
139
# **Question:**
What are the two main clinical manifestations of atherosclerosis **at the abdominal aorta**?
Typically, extensive atherosclerotic plaques can led to **aneurismal dilatation** and subsequent **aortic rupture**.
140
# **Question:**
What is the main clinical manifestation of atherosclerosis **at the legs**?
Renal vessels constriction can
cause **renovascular hypertension**.
141
# **Question:**
What is the main clinical manifestation of atherosclerosis **at the legs**?
Atherosclerotic plaques can result in **intermittent claudication**, i.e., fatigue and pain that worsen on walking and are relieved at rest.
142
# **Complete the sentence:**
Hypertension is called ________________ hypertension, if it has multiple known causes, or ____________ hypertension if the cause is unknown.
secondary, essential
## Footnote
Essential hypertension can also be called idiopathic or primary hypertension.
143
# **Question:**
What are the four main factors associated with hypertension?
Hypertension is mostly associated with:
1. **Increased peripheral vascular resistance** (due to vasoconstriction or endothelial dysfunction).
2. **Increased cardiac output** (higher heart rate or stroke volume).
3. **Increased blood volume** (due to excess sodium and water retention).
4. **Increased blood viscosity** (which increases resistance to blood flow).
144
# **Question:**
What are the clinical manifestations?
Hypertension mostly presents nonspecific symptoms such as headaches, fatigue and dizziness.
Nevertheless, when not treated it can result in other complications, such as heart failure, myocardial ischemia and infarction, aneurysms, retinopathy, hemorrhagic stroke, renal failure, etc.
145
# **Question:**
How can hypertension lead to heart failure?
Hypertension corresponds to high arterial pressure. This leads to increased afterload, which is the pressure that the heart must work against to eject blood during systole (ventricular contraction), therefore leading to systolic dysfunction. Additionally, in order to be able to support such high arterial pressure, the left ventricle (LV) wall thickness, leading to LV hypertrophy, which ultimately will impair ventricle relaxation during filling, resulting in diastolic dysfunction. The combination of both diastolic and systolic dysfunction will induce heart failure. Heart failure occurs when the heart muscle doesn't pump blood as well as it should.
146
# **Question:**
How can hypertension lead to myocardial ischemia and infarction?
Myocardial infarction, colloquially known as "heart attack," is caused by decreased or complete cessation of blood flow to a portion of the myocardium. Hypertension (high arterial blood pressure) may lead to arterial damage, which accelarates atherosclerosis, specially in coronary vessels (that irrigate the myocardium), leading to decreased myocardial blood and oxygen supply and, therefore, myocardial ischemia and infarction.
147
# **Question:**
What are the risk factors of hypertension?
* Gender
* Obesity
* Lack of Physical Activities
* Age
* Genetic
* Stress and Anxiety
* Sodium consumption
* Alcohol consumption
* Smoking
* Caffeine
148
# **Quetion:**
Why is high sodium intake a risk factor for hypertension?
High sodium intake increases water retention, leading to higher blood volume and increased cardiac output. It also enhances vascular resistance by promoting vasoconstriction and reducing endothelial function. These effects contribute to sustained high blood pressure and increase the risk of hypertension.
149
# **Question:**
What is circulatory shock?
Condition associated to an inadequate tissue perfusion in consequence of inadequate cardiac output or inadequate volemia inside blood vessels.
150
# **Question:**
What are the four main types of circulatory shock?
1. Hypovolemic shock
2. Distributive or vasogenic shock
3. Cardiogenic shock
4. Obstructive shock
151
# **Question:**
What is hypovolemic shock?
Inadequate tissue perfusion due to **reduced blood volume**.
152
# **Question:**
In which scenarios can hypovolemic shock occur?
Can occur in scenarios of hemorrhage, trauma, surgery, burns or severe fluid loss (diarrhea and vomiting).
153
# **Question:**
What is distributive or vasogenic shock?
Inadequate tissue perfusion when there is a **general marked vasodilatations**, despite the blood volume remains the same.
154
# **Question:**
In which scenarios can distributive or vasogenic shock occur?
Can occur in scenarios of fainting,
anaphylaxis or sepsis.
155
# **Question:**
What is cardiogenic shock?
Inadequate tissue perfusion when there is an **inadequate cardiac output due to myocardial abnormalities**.
156
# **Question:**
When can cardiogenic shock occur?
Can occur in scenarios of myocardial infarction, heart failure or arrythmias.
157
# **Question:**
What is obstructive shock?
Inadequate tissue perfusion when there is an **inadequate cardiac output due to an obstruction** of the blood flow in the lungs or heart.
158
# **Question:**
When can obstructive shock occur?
Can occur in scenarios of tension pneumothorax, pulmonary embolism, cardiac tumor or pericardial tamponade.
159
# **Complete the sentence:**
Circulatory shock occurs when there is a ____________ (hyperperfusion/hypoperfusion) of tissues, usually accompanied by ________________ (hypertension/hypotension) and ________________ (tachycardia/bradycardia).
hypoperfusion, hypotension, tachycardia
160
# **Question:**
Which of the types of circulatory shock presents a normal or high cardiac output?
Distributive or vasogenic shock
161
# **Complete the sentence:**
Distributive or vasogenic shock usually presents with a ____ (high/low) cardiac output, while hypovolemic, cardiogenic and obstructive shocks present with a ____ (high/low) cardiac output.
high, low
162
# **Question:**
Why are lactate levels usually elevated in patients suffering a circulatory shock?
In circulatory shock, tissue hypoperfusion leads to insufficient oxygen delivery to cells. This forces cells to switch from aerobic metabolism to anaerobic glycolysis, which generates lactate as a byproduct. The accumulation of lactate indicates tissue hypoxia and impaired oxidative metabolism.
