PBL Flashcards
what initiates the excitement of the heart
sino-atrial node
what does stroke volume respond to changes in
pre-load and after load (frank-starling curve)
what heart conditions can inherited
cardiomyopathies, inherited arrhythmias (LQTS, brugada), very high cholesterol levels
what should waist circumference be for men and women
men less than 94cm
women less than 80 cm
what should BMI be
18.5-24-9 healthy
more than 30 = obese
what are the three layers of the pericardium and which one is in contact with the heart
outermost- fibrous, parietal serous, visceral serous- innermost in contact with the heart
what is between the serous layers of the pericardium
pericardial space filled with pericardial fluid
where are the semilunar valves of the heart
at the base of the great vessels
where do most of the coronary veins drain into
the coronary sinus which drains into the right atrium
where are baroreceptors located and what are they sensitive to
located in the walls of the large arteries and are stretch receptors which are sensitive to changes in pressure
how do baroreceptors respond to changes in blood pressure
cause reflex changes to bring blood pressure back to normal
how does an increased arterial BP affect the medulla
an increased arterial BP causes an increase in action potential frequency to the cardio-regulatory centres in the medulla, causing an increase in parasympathetic activity to the heart, decreasing HR and force of contraction
how do chemoreceptors maintain BP
by monitoring blood oxygen, CO2 and pH. if decreased O2 or pH or increased CO2 or pH the chemo-receptors will cause a decrease in para symp stim
what are the natural mechanisms for long term BP maintenance
pressure natriuresis, RAA mechanism, ADH mechanism and natriuretic peptide hormone
what is pressure diuresis
increased urine output due to high arterial pressure- decreases blood volume
what is pressure natriuresis
increased sodium output due to high BP- decreases blood volume
what is the RAA mechanism and how does it control BP
renin-angiotensin-aldosterone
regulates kidney function which affects peripheral resistance, blood volume and blood pressure
when is renin secreted and from where
released from kidney when BP is reduced
what is the role of renin
cleaves protein angiotensin to angiotensin 1 which is later cleaved to angiotensin 2
also acts on adrenal cortex to secrete aldosterone which acts on kidney tubules to increase reabsorbtion of sodium- increasing blood volume
what does angiotensin 2 do
constricts arterioles and veins to increase venous return to the heart and increase arterial BP
what is ADH and when is it released
anti-diuretic hormone
when baroreceptors detect decrease in arterial blood pressure
what does ADH do
acts directly on blood vessels causing vasoconstriction and increases water absorption by the kidneys - increasing BP
what releases natriuretic peptides and when
synthesised by the heart, brain and other organs
released in response to cardiac distension or neurohormonal stimuli
what do natriuretic hormones do
cause excretion of salt and water in the kidneys - reducing blood volume
also decrease renin release and act as vasodilators
what are ‘gallop’ heart sounds
low frequency sounds associated with diastolic filling
where do you measure waist circumference and what does it show
between lower rib and iliac spine
distribution of fat
what are the normal ranges for cholesterol
LDL below 5
HDL above 1
what are the clinical signs of hypertension
loud aortic second sound, prominent left ventricular impulse, fourth heart sound, hypertensive retinopathy
describe the grading of hypertensive retinopathy
grade 1 slight narrowing
grade 3 exudates or flame haemorrhages
grade 4 optic nerve oedema
why is being female important in CV history
menopause, combined oral contraceptive pill
what drugs are used to treat hypertension
ace inhibitor, ARB, calcium channel blocker, thiazide like diuretic,
when should fibrates be given
patients with very high triglyceride levels
what does a loud second aortic sound suggest
systemic hypertension with a dilated proximal aorta (loud pulmonary sound would show pulmonary hypertension)
what trophic features are associated with limb ischaemia
cold feet hair loss shiny pale skin poor or absent pulses ulcers gangrene of toes amputations
are ARBs and ACEis safe in pregnancy
no
what is the ventricular rate in atrial flutter
17/150
what are the common causes of peripheral vascular disease
smoking, hypercholesteraemia, hypertension, diabetes
what drug treatment is used for hyperlipidaemia
statins or fibrates
how does diabetes affect NO levels
reduces them = bad
why does high levels of glucose in the blood accelerate the atherosclerotic process
as if a pro inflammatory mediator
how do beta blockers work
completely inhibit the binding of noradrenaline to B1 adrenoceptors in the sympathetic system, resulting in less forceful contractions
when is ivabradine used and what does it do
alongside beta blockers in angina
blocks HCN channels, delaying pacemaker potential and slowing HR
what drugs should never be given together
beta blocker and calcium channel antagonist
what are the types of necrosis
coagulative, caseous, fat, fibroid, gangrenous
what is the difference between athero and arterio sclerosis
athero lifestyle, lipid build up
arterio purely BP
what are the causes of acute severe chest pain
acute coronary syndromes including myocardial infarction pulmonary embolism aortic dissection pneumothorax herpes Zoster pericarditis
what are the mechanical complications of an MI
acute left ventricular failure cardiogenic shock cardiac rupture pericardial tamponade ventricular aneurysm ventricular septal defect mitral regurgitation
what is the treatment for an acute MI
Morphine + anti emetic
Oxygen
Nitroglycerin
Aspirin
tricagrelor
thrombolysis if PCI if more that 120 mins from hospital
why is CK levels not completely trustworthy
can be raised in lots of conditions
how is pulmonary oedema seen on a CXR
ABCDE of pulmonary oedema on CXR: A - Alveolar oedema (Bat’s wings), B - Kerley B lines (interstitial oedema), C - Cardiomegaly, D - Dilated prominent upper lobe vessels, E - Pleural effusion
what is acyanotic heart disease
class of congenital heart disease where blood is shunted from the left to the right
- atrial septal defect
- ventricular septal defect
name 4 ventricular septal defects
Patent ductus arteriosus
Aortic stenosis
Coarctation of the aorta
Pulmonary stenosis
give examples of cyanotic congenital heart disease
Fallots and etology
Transposition
Ebstein’s Anomaly (with ASD)
Hypoplastic left heart
Total anomalous pulmonary venous drainage
Tricuspid or pulmonary artesia
how are cardiomyopathies classified
Hypertrophic
Idiopathic dilated
Restrictive
Alcohol associated
what are cardiac causes of shortness of breath
Cardiac failure Valvular heart disease Obstructive airways disease Restrictive lung disease Pulmonary hypertension Pulmonary embolism Anaemia
what can cause cardiac valve disease
Congenital Rheumatic Ischaemic Degenerative Infective Miscellaneous
what conditions predispose to infective endocarditis
Valvular heart disease
Prosthetic heart valves
Congenital heart disease
what can cause atrial fibrillation
Rheumatic heart disease Ischaemic heart disease Thyrotoxicosis Alcohol Hypertension Lone atrial fibrillation
what is rheumatic heart disease
Rheumatic fever is an inflammatory disorder caused by Group A strep throat infection. This may progress to rheumatic heart disease, wherein one or more heart valves are damaged or scarred in the process.
what are the clinical signs of rheumatic heart disease
tapping apex beat- mitral stenosis
AF
how does rheumatic heart disease cause AF
Increased preload due to mitral stenosis, thus the atria are stretched. This causes erratic electrical activity.
name this murmur:
Crescendo-decrescendo, ejection systolic murmur, radiating to the carotids
aortic stenosis
name this murmur:
Decrescendo early-diastolic murmur.
aortic regurgitation
name this murmur:
Low-pitch, mid-diastolic murmur with opening snap.
mitral stenosis
name this murmur:
Harsh, pansystolic murmur radiating to axilla
mitral regurgitation
name this murmur:
High-pitched, holosystolic radiating to right lower sternal border
tricuspid regurgitation
what do loop diuretics do
leads to the excretion of water from the body
what do thiazide diuretics do
promote potassium excretion but inhibit calcium excretion
what drugs are used to treat heart failure
diuretics, beta blockers (reduces HR and BP), ace inhibitors (reduced BP), spironolactone (Aldosterone receptor antagonist), ivabradine (HCN blocker)
what is a transthoracic echo
shows heart motion and structure as sound waves directed at heart across chest
what is a transesophageal echo
closer look at valves as scanner down oesophagus
what are C-reactive protein and plasma viscosity tests for
inflammation, higher the levels the more active the disease
what is tetralogy of fallot
congenital heart disease = made up of ventricular septal defect, pulmonary stenosis, RVH and a displaced aorta. This causes mixing of oxygenated and non-oxygenated blood leading to cyanosis
what is pericarditis
inflammation of the pericarditis
what can cause pericarditis
- Myocardial infarction (Dressler’s syndrome)
- Systemic inflammatory disorders e.g. lupus and rheumatoid arthritis.
- Trauma to your heart or chest
- Kidney failure
- AIDS
- Tuberculosis
- Cancer
- Medications although this is unusual
