Monday Lobs Flashcards
1
Q
Outline what will cause the following deflections on an ECG
- Positive
- Negative
- No Deflection
A
- Depolarisation in the direction of electrode
- Depolarisation away from the electrode
- Depolarisation perpendicular to the electrode
2
Q
Draw a diagram of a lead 2 waveform with heart diagrams
A
3
Q
Draw the badass heart/ech/phono/ventricular pressure diagram with labels of each section of the cardiac cycle
A
4
Q
Which waves give rise to:
- Atrial Depolarisation
- Atrial Repolarisation
- Ventricular Depolarisation
- Ventricular Repolarisation
A
- P Wave
- Can’t be seen (hidden by QRS complex)
- QRS Complex
- T Wave
5
Q
Which combo of leads tells us about the right ventricle?
A
6
Q
Which combo of leads can tell us about the basal septum?
A
7
Q
Which combo of leads tells you about the Left Lateral wall of the Heart?
A
V5-V6, (+1 & AVL)
8
Q
Which combo of leads tells us about the anterior wall of the heart?
A
V2-V4
9
Q
Which leads tells you about the High Lateral Left Wall of the heart?
A
I & AVL
10
Q
Which combo of leads tells you about the inferior wall of the heart?
A
II, III and AVF
11
Q
Draw a diagram to show the placement/viewpoint of each of the leads I-III, and the AVF/L/R.
A
12
Q
Draw the placement of leads V1-V6
A
13
Q
Draw a flow chart outlining the RAAS system effects on maintaining homeostasis upon baroreceptor detection of Hypotension
A
14
Q
What is the formula for Cardiac Output?
A
CO = Stroke Volume x Heart Rate
15
Q
What is the formula for Blood Pressure?
A
BP = Cardiac Output x Total Peripheral Resistance
16
Q
Which nerves do the baroreceptors in the following vessels stimulate/inhibit?
- Aortic Sinus
- Carotid Sinus
A
- Vagus Nerve
- Glossopharyngeal Nerve
17
Q
The Vagus and Glossopharyngeal nerve stimulate which area in the Medulla?
A
The Nucleus of Tractus Solitarius
18
Q
The N of TS can stimulate or inhibit 3 differenct nerve centres in the medulla.
- CAC
A
Cardiac Accelatory Centre
- Activates pre ganglionic fibers at T1-L2 in the lateral grey column
- Causes release of Norepinephrine at SA and AV nodes in the heart
- Increases activity of If channels, thereby allowing the threshold for V-Gated Ca+ channels to open. Happens via GaS-protein receptor mechanism, and increases heart rate
- Also releases NE into the myocardium of the heart, and via GaS - induced CICR from Ca+ stores in the Sarcoplasmic Reticulum (via ryanodine receptors) increases the number of cross-bridges through troponin. This creates a positive chronotropic effect.
- Simultaneously NE at GaS receptors in the myocardium produce a Lusotropic effect of ventricular relaxation as PKA rapid stimulates K+ release - leading to rapid repolarization and the restoring of Ca+ in the SR.
- Stimulates chromaffin cells of the adrenal medulla to release 80% Epi and 20% NE (acts as above)
19
Q
The N of TS can stimulate or inhibit 3 different nerve centres in the medulla.
- VMC
A
Vaso Motor Centre
- Pre-ganglionic fibres from the thoracolumbar region of the spinal column to the Tunica Media of the blood vessels
- Releases NE to increase calcium permeability and stimulate Vasoconstriction
20
Q
Explain how the Cardiac Inhibitory centre evokes a decrease in heart rate. Include a diagram
A
Cardiac Inhibitory Centre
- Part of the dorsal nucleus of the Vagus Nerve (cranial nerve 10)
- Innervates the SA and AV nodes
- Ach Muscarinic Type 2 receptors activate a G2 inhibitory protein
- alpha subunit inhibits If channel activity, harder to reach threshold for Ca channels so less action potentials and therefore less cross bridges
- beta/gamma subunits open K channels to cause Hyperpolarisation of the cell, far harder to cause action potentials.
21
Q
Define Positive and Negative Chronotropic action
A
Encourage an increase (+) or decrease (-) in heart rate
22
Q
What is the inhibitory chemical released by the heart that counteracts the effects of Angiotensin II?
Give a name, description of origin and physiological function
A
ANP = Atrial Naturietic Peptide
Secreted by the endocrine cells of the Left Atria in response to stretching
Inhibits almost all effect of Angiotensin II
23
Q
Draw a diagram of the effect of Aldosterone on the DCT
A
24
Q
What is an NHS Check?
A
The NHS Health Check is a preventive healthcare programme offered by Public Health England. The programme invites adults aged between 40 and 74 in England for a health check-up every five years, to screen for key conditions, including heart disease, diabetes, kidney disease, and stroke.[1]
During the check-up you’ll also discuss how to reduce your risk of these conditions and dementia.
The health professional – often a nurse or healthcare assistant – will ask you some questions about your lifestyle and family history, measure your height and weight, and take your blood pressure and do a blood test. The blood test will be done either before the check with a blood sample from your arm, or at the check.
You will then receive personalised advice to improve your risk.
25
Why did Sandra change to the progesterone only pill
Smokers can use most types of contraception. But if you're a smoker and over 35 years old, some contraceptives (such as the combined pill, patch or the vaginal ring) might not be suitable for you.
26
What is arteriosclerosis?
Arteriosclerosis occurs when the arteries become thick and stiff — sometimes restricting blood flow to your organs and tissues. Healthy arteries are flexible and elastic, but over time, the walls in your arteries can harden.
27
What is atherosclerosis?
Atherosclerosis is a specific type of arteriosclerosis.
Atherosclerosis is the buildup of fats, cholesterol and other substances in and on your artery walls. This buildup is called plaque. The plaque can cause your arteries to narrow, blocking blood flow. The plaque can also burst, leading to a blood clot.
28
Name 3 distinct features of retinal blood vessel that differentiate them from others.
* The absence of sympathetic nerve supply
* Auto-regulation of blood flow
* Presence of blood-retinal barrier
29
Draw a diagram of a healthy fundus, and one suffering from Hypertensive Retinopathy
30
Sally Thompson has Stage 2 Hypertensive Retinopathy. What are the features of each stage?
* Stage 1: Mild narrowing of the arterioles
* Stage 2: Focal constriction of blood vessels and AV nicking
* Stage 3: Cotton-wool patches, exudates and haemorrhages
* Stage 4: Papilloedema
31
Explain how each layer of the fundus blood vessels are affected by HTN, and how that leads to Silver Wiring and AV Nipping
Persistent increase in BP causes certain changes in vessel wall:
* Intima layer: Thickening
* Media layer: Hyperplasia
* Arteriolar wall: Hyaline degeneration
This leads to a severe form of arteriolar narrowing, arteriovenous (AV) crossing changes, and widening and accentuation of light reflex (silver and copper wiring). AV crossing changes occur when a thickened arteriole crosses over a venule and subsequently compresses it as the vessels share a common adventitious sheath. The vein, in turn, appears dilated and torturous distal to the AV crossing.
32
What is the difference between hyperplasia and hypertrophy?
Hyperplasia refers to the process where cells in an organ or tissue increase in number, so its like hiring a bigger pack of lumberjacks.
Hypertrophy is when these cells in an organ or tissue increase in size, like if the lumberjack gets really tough so that she can cut down twice as many trees.
33
Draw a diagram to describe the arterial blood flow to different sections of the heart
34
Describe the overall effects of the SNS and PNS on HTN in table format
35
Outline the different criteria for Stage 1, 2, and 3 HTN
36
What are the modifiable risk factors for HTN and why?
* **Being overweight or obese.** The more you weigh, the more blood you need to supply oxygen and nutrients to your tissues. As the amount of blood flow through your blood vessels increases, so does the pressure on your artery walls.
* **Not being physically active.** People who are inactive tend to have higher heart rates. The higher your heart rate, the harder your heart must work with each contraction and the stronger the force on your arteries. Lack of physical activity also increases the risk of being overweight.
* **Using tobacco.** Not only does smoking or chewing tobacco immediately raise your blood pressure temporarily, but the chemicals in tobacco can damage the lining of your artery walls. This can cause your arteries to narrow and increase your risk of heart disease. Secondhand smoke also can increase your heart disease risk.
* **Too much salt (sodium) in your diet.** Too much sodium in your diet can cause your body to retain fluid, which increases blood pressure.
* **Too little potassium in your diet.** Potassium helps balance the amount of sodium in your cells. A proper balance of potassium is critical for good heart health. If you don't get enough potassium in your diet, or you lose too much potassium due to dehydration or other health conditions, sodium can build up in your blood.
**Drinking too much alcohol.** Over time, heavy drinking can damage your heart. Having more than one drink a day for women and more than two drinks a day for men may affect your blood pressure.
If you drink alcohol, do so in moderation. For healthy adults, that means up to one drink a day for women and two drinks a day for men. One drink equals 12 ounces of beer, 5 ounces of wine or 1.5 ounces of 80-proof liquor.
* **Stress.** High levels of stress can lead to a temporary increase in blood pressure. Stress-related habits such as eating more, using tobacco or drinking alcohol can lead to further increases in blood pressure.
37
What are the non-modifiable risk factors for HTN?
* **Age.** The risk of high blood pressure increases as you age. Until about age 64, high blood pressure is more common in men. Women are more likely to develop high blood pressure after age 65.
* **Race.** High blood pressure is particularly common among people of African heritage, often developing at an earlier age than it does in whites. Serious complications, such as stroke, heart attack and kidney failure, also are more common in people of African heritage.
* **Family history.** High blood pressure tends to run in families.
38
What is the difference between Primary and Secondary Hypertension?
39
Draw the effects of AN2 on the DCT
40
What are the limits of a normal heart rate?
Normal 60-100
Bradycardic \<60
Tachycardic\>100
41
What are the two methods for determining heart rate on an ECG?
1. On a 10-second strip (50 Big boxes) simply count the number of R waves and multiply by 6
2. See picture:
42
What is Atrial Fibrillation and how does it present on an ECG?
**Atrial fibrillation** (**AF** or **A-fib**) is an [abnormal heart rhythm](https://en.wikipedia.org/wiki/Heart_arrhythmia) (arrhythmia) characterized by [rapid and irregular beating](https://en.wikipedia.org/wiki/Fibrillation) of the [atrial chambers of the heart](https://en.wikipedia.org/wiki/Atrium_(heart)).
It presents as an Irregular Arrhythmia on the Rhythm strip
43
What are the features of Normal Sinus Rhythm on an ECG
44
How do the following types of heart block appear on an ECG?
1. First Degree
2. Second Degree Type 1
3. Second Degree Type 2
Third Degree
1. A PR Interval \> 0.2 seconds (5 small squares)
2. Progressive prolongation of the PR interval until eventually the atrial impulse is not conducted and the QRS complex is dropped. AV nodal conduction resumes with the next beat and the sequence repeats
3. Consistent PR interval duration with intermittently dropped QRS complexes due to a failure of conduction.
Typically follows a repeating cycle of every 3rd (3:1 block) or 4th (4:1 block) P wave.
4.Complete dissociation between Atrial and Ventricular activity
45
What are possible pathologies indicated by inverted T waves (in leads other than V1 and III)
* Ischaemia
* Bundle branch blocks (V4-6 in LBBB and V1-V3 in RBBB)
* Pulmonary embolism
* Left ventricular hypertrophy (in the lateral leads)
* Hypertrophic cardiomyopathy (widespread)
* General illness
Around 50% of patients admitted to ICU have some evidence inverted T waves.
46
What is the criteria of a Tall T Wave and what can it indicate?
T waves are considered **tall** if they are:
* **\> 5mm** in the **limb leads** AND
* **\> 10mm** in the **chest** **leads** (the same criteria as ‘small’ QRS complexes)
Tall T waves can be associated with:
* **Hyperkalaemia** (“tall tented T waves”)
* **Hyperacute** **STEMI**
47
What are the criteria and pathological indications of:
ST Elevation
ST Depression
**ST-elevation** is significant when it is **greater than 1 mm** (1 small square) **in 2 or more contiguous limb leads** or **\>2mm in 2 or more chest leads**.
It is most commonly caused by **acute full-thickness myocardial infarction**.
**ST depression** **≥ 0.5 mm** in **≥ 2 contiguous leads** indicates **myocardial** **ischaemia**.
48
What constitutes a Tall or Broad R wave? And what pathologies do they signify?
Broad is \> 0.12
A **broad QRS complex** occurs if there is an abnormal depolarisation sequence
Tall is \> 0.5 in limb and \> 0.10 in chest leads
**Tall** **complexes** imply ventricular hypertrophy
49
Draw a MICCA table for ACEi
50
Draw a MICCA table for ARBs
51
Draw a MICCA table for CCBs
52
Draw a MICCA table for Thiazide-like Diuretics
53
Draw a MICCA table for Alpha Blockers
54
Draw a MICCA table for Beta Blockers
55
Draw the NICE Guidelines regarding pharmacological and patient education treatment for HTN
56
What is the key for time and voltage on the little squares on an ECG
57
Cholesterol is an organi
Cholesterol is an organic Lipid sterol
It is a key component of arterial plaques, and therefore in the pathogenesis of Atherosclerosis
58
What are LDL and HDL?
HDL and LDL are two types of lipoproteins.
They are a combination of fat (lipid) and protein. The lipids need to be attached to the proteins so they can move through the blood.
HDL and LDL have different purposes:
HDL stands for high-density lipoproteins. It is sometimes called the "good" cholesterol because it carries cholesterol from other parts of your body back to your liver. Your liver then removes the cholesterol from your body.
LDL stands for low-density lipoproteins. It is sometimes called the "bad" cholesterol because a high LDL level leads to a buildup of cholesterol in your arteries.
59
What is HbA1c?
Glycated hemoglobin (HbA1c) is a form of hemoglobin that is chemically linked to a glucose molecule.
The formation of the sugar-hemoglobin linkage indicates the presence of excessive sugar in the bloodstream, often indicative of [diabetes](https://en.wikipedia.org/wiki/Diabetes).
Also causes oxidative stress and contributes to Atherosclerosis
60
Summarise the Frank-Starling Law
The greater the ventricular diastolic volume, the more the myocardial fibers are stretched during diastole. Within a normal physiologic range, the more the myocardial fibers are stretched, the greater the tension in the muscle fibers and the greater force of contraction of the ventricle when stimulated. The Frank-Starling relationship is the observation that ventricular output increases as preload (end-diastolic pressure) increases.
61
What are the normal Systolic/Diastolic pressures in the different parts of the heart?
62
What is End Diastolic Volume and End Systolic Volume, and how can stroke volume be calculated from that?
63
What is the normal SV/EDV ratio?
64
Discuss the Ventricular Volume-Pressure loop, and show how it can demostrate stroke volume vs pressure.
How is it altered in:
1. Exercise
2. Hypertension
65
Discuss the pulsatile pressures of atrial contraction (A-X-V-Y)
Note: Can be seen as raised JVP in CV exam if atria is having to overcome greater ventricular pressure.
66
What are the different heart sounds?
S1 - Tri/Mit Valves Closing
S2 - Pul/Aor Valves Closing
67
True or False: Blood Vessels constrict during exercise?
False: They dilate so as to lower TPR
68
Outline the role of troponin in muscle contractility
Troponin is attached to the protein [tropomyosin](https://en.wikipedia.org/wiki/Tropomyosin) and lies within the groove between [actin](https://en.wikipedia.org/wiki/Actin) filaments in muscle tissue. In a relaxed muscle, tropomyosin blocks the attachment site for the [myosin](https://en.wikipedia.org/wiki/Myosin) [crossbridge](https://en.wikipedia.org/wiki/Crossbridge), thus preventing contraction. When the muscle cell is stimulated to contract by an [action potential](https://en.wikipedia.org/wiki/Action_potential), [calcium channels](https://en.wikipedia.org/wiki/Calcium_channels) open in the sarcoplasmic membrane and release calcium into the sarcoplasm. Some of this calcium attaches to troponin, which causes it to change shape, exposing binding sites for myosin (active sites) on the [actin](https://en.wikipedia.org/wiki/Actin) [filaments](https://en.wikipedia.org/wiki/Protein_filament). [Myosin](https://en.wikipedia.org/wiki/Myosin)'s binding to actin causes [crossbridge](https://en.wikipedia.org/wiki/Crossbridge) formation, and contraction of the muscle begins.[[5]](https://en.wikipedia.org/wiki/Troponin#cite_note-5)
69
Define Calcium-Induced Calcium Release (CICR)
**A process whereby an influx of calcium can trigger release of further calcium from the muscle sarcoplasmic reticulum, by inflowing Ca+ binding to ryanodine receptors and stimulating more calcium release from the stores.**
70
Draw a diagram to outline the effects of NE in the myocytes - INOTROPICALLY
71
Draw a diagram to outline the effects of NE in the myocytes - LUSOTROPICALLY
72
Draw a diagram to outline the effects of NE at the SA and AV nodes - CHRONOTROPICALLY
73
Draw a diagram to outline the effects of the SNS on increasing rate and strength of action potentials
74
How does venoconstriction affect CO?
75
Draw a diagram to outline the effects of NE in the smooth muscle of blood vessels - at G*a*Q Receptors
Note: The specific mechanism for activating phosphorylated actin is as follows:
Ca binds to calmodullin
Calmodullin+Ca activates Myosin Light Chain Kinase
Calmodullin+Ca+MLCK activates Myosin Light Chain
Mysolin Light Chain phosphorylates Myosin heads, to allow cross-bridge formation with actin.
76
Draw a more detailed diagram of the baroreceptor activation of RVLM via switching off of inhibatory CVLM
77
In Pharmacokinetics, what is Volume of Distribution?
Vd is a *proportionality constant* that relates the total amount of drug in the body to the plasma concentration of the drug at a given time.
Volume of Distribution (L) = Amount of drug in the body (mg) / Plasma concentration of drug (mg/L)
Based on the above equation:
A drug with a **high** **Vd** has a propensity to leave the plasma and enter the extravascular compartments of the body, meaning that a **higher dose** of a drug is required to achieve a given plasma concentration. (High Vd -\> More distribution to other tissue)
Conversely, a drug with a **low** **Vd** has a propensity to remain in the plasma meaning a **lower dose** of a drug is required to achieve a given plasma concentration. (Low Vd -\> Less distribution to other tissue)
78
What are the four stages of Drug movement in the body?
79
# Define the following terms in the context of drug administration:
1. Buccal
2. Sublingual
3. Enteral
4. Parenteral
5. Intradermal
6. Intrathecal
7. Epidural
8. Topical/Transdermal
1. Administered in the mucous membrane of the mouth
2. Administered under the tongue
3. Administered via the GI Tract
4. Administered so as to bypass the GI Tract
5. Subcutaneous injections are administered in the fat layer, underneath the skin. Intradermal injections are delivered into the dermis, or the skin layer underneath the epidermis.
6. Administered in the CS Fluid of the spinal cord
7. Administered into the dura matter of the spinal cord
8. Administered on the surface of the skin
80
Draw a diagram to outline the journey a drug takes from an enteral route, and show how other forms of administration can bypass this route to increase velocity of action.
81
What 4 things do we consider when choosing method of drug administration?
82
Give a definition, diagram, and formula for Bioavailability
83
Discuss what the Kc of a drug is in the context of drug distribution between compartments, give reasons for differences and include a diagram
84
What factors influence Volume of Distribution?
85
Why can you have Hypotension AND Tachycardia?
**Tachycardic**
The lack of adequate diastolic time means lower refilling of ventricles and decreases CO
86
What is the distribution of blood in our circulatory system?
13% Arteries
6% Capillaries
81% Venous System
NB: Only 10-15% of capillaries are open or active at any time
87
What percentages of salt/electrolytes are absorbed in which parts of the nephron?
88
Where are baroreceptors for Hyper and Hypo tension located?
88
Why is the Aorta considered a ‘Pressure Reservoir'?
