Monday Lobs Flashcards
Outline what will cause the following deflections on an ECG
- Positive
- Negative
- No Deflection
- Depolarisation in the direction of electrode
- Depolarisation away from the electrode
- Depolarisation perpendicular to the electrode
Draw a diagram of a lead 2 waveform with heart diagrams
Draw the badass heart/ech/phono/ventricular pressure diagram with labels of each section of the cardiac cycle
Which waves give rise to:
- Atrial Depolarisation
- Atrial Repolarisation
- Ventricular Depolarisation
- Ventricular Repolarisation
- P Wave
- Can’t be seen (hidden by QRS complex)
- QRS Complex
- T Wave
Which combo of leads tells us about the right ventricle?
Which combo of leads can tell us about the basal septum?
Which combo of leads tells you about the Left Lateral wall of the Heart?
V5-V6, (+1 & AVL)
Which combo of leads tells us about the anterior wall of the heart?
V2-V4
Which leads tells you about the High Lateral Left Wall of the heart?
I & AVL
Which combo of leads tells you about the inferior wall of the heart?
II, III and AVF
Draw a diagram to show the placement/viewpoint of each of the leads I-III, and the AVF/L/R.
Draw the placement of leads V1-V6
Draw a flow chart outlining the RAAS system effects on maintaining homeostasis upon baroreceptor detection of Hypotension
What is the formula for Cardiac Output?
CO = Stroke Volume x Heart Rate
What is the formula for Blood Pressure?
BP = Cardiac Output x Total Peripheral Resistance
Which nerves do the baroreceptors in the following vessels stimulate/inhibit?
- Aortic Sinus
- Carotid Sinus
- Vagus Nerve
- Glossopharyngeal Nerve
The Vagus and Glossopharyngeal nerve stimulate which area in the Medulla?
The Nucleus of Tractus Solitarius
The N of TS can stimulate or inhibit 3 differenct nerve centres in the medulla.
- CAC
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)
The N of TS can stimulate or inhibit 3 different nerve centres in the medulla.
- VMC
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
Explain how the Cardiac Inhibitory centre evokes a decrease in heart rate. Include a diagram
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.
Define Positive and Negative Chronotropic action
Encourage an increase (+) or decrease (-) in heart rate
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
ANP = Atrial Naturietic Peptide
Secreted by the endocrine cells of the Left Atria in response to stretching
Inhibits almost all effect of Angiotensin II
Draw a diagram of the effect of Aldosterone on the DCT
What is an NHS Check?
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.
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.
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.
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.
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
Draw a diagram of a healthy fundus, and one suffering from Hypertensive Retinopathy
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
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.
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.
Draw a diagram to describe the arterial blood flow to different sections of the heart
Describe the overall effects of the SNS and PNS on HTN in table format
Outline the different criteria for Stage 1, 2, and 3 HTN