Valves and Kidney Drugs Flashcards
In stenosis, pressure is higher in the chamber behind? or in front of the valve?
behind the valve
What kind of overload is in stenosis? which chamber?
Pressure overload in the chamber behind the valve.
How do you get volume overload?
valve incompetence/regurgitation
What is innocent flow murmurs?
benign turbulence caused by high flow in children, fever, preg
2 Main causes of Valvular Heart Disease?
degenerative
congenital
Rheumatic fever (past)
What are the symptoms for mild/moderate valve lesions?
asymptomatic
When symptoms develop for regurg valve disease, is it reversible?
usually poor prognosis, irreversible canoes to LV
If you have symptoms for aortic stenosis, is it reversible?
Yes, LV changes can regress
What’s most important besides history to diagnose valvular heart disease?
Echocardiography because can show changes before irreversible
Valvular heart disease interventions. 4 of them
Replacements: metal/plastic
repair
balloon valvotomy
stent valves
What is the normal pressure gradient across valves?
0mm Hg
What is normal valve area?
> 2.5cm2
What kind of aortic stenosis usually in elderly?
calcific
What causes aortic leaflet damage? 2 reasons
- Endocarditis
2. Rheumatic fever
What causes aortic root dilation? 4 reasons.
Marfan’s
Aortic dissection
collagen vascular disorder (AS)
syphillis (past)
When does aortic regurgitation occur?
during diastole
what’s a consequence of aortic regurgitation?
volume overload for LV
increase EDV, EF, SV
Normal ESV
in aortic regurgitation, what does the pulse feel like?
collapsing pulse
Are decompensation changes in aortic regurgitation reversible
No.
How to treat acute severe aortic regurgitation?
early surgery due to cardiogenic shock/acute pulmonary oedema.
what does cardiomyopathy do to mitral valve?
changes the ventricular shape as who heart is bigger, not al structures are proportional = mitral regurg
what happens to left atrium in mitral regurgitation?
increase LA volume and pressure
Are heart changes reversible in mitral regurgitation?
Nope. Not after decompensation.
Why would you get left atrial fib?
left atrial pressure and volume increase, atrium stretches
Symptoms of Right heart failure?
pulmonary hypertension, congestion, oedema, hypoxia
When would the risk of a thrombus in the Left atrium be significant?
mitral regurgitation
When is the ‘atrial kick’ important? increases risk of what?
in Mitral Stenosis
Thrombosis
fibrillation
is left ventricular systolic function affected in Mitral Stenosis?
Nope. Aaaaalll Atria baby.
4 things kidney does
regulate water and salt
endocrine
excrete endogenous waste
excret exogenous waste
Drug elimination has two things:
metabolism
excretion
Where is K+ secreted? 2 spots
Collecting ducts
Distal tubule
how do you treat aspirin overdose?
sodium bicarb
3 kinds of drugs act on the kidney:
- diuretics
- urine pH
- alter secretion of organic molecules
Diuretics do what exactly?
Increase Na+ and Cl- excretion
4 types of diuretics are:
- loop
- thiazide
- K+ sparing
- osmotic
Which is the most powerful class of ‘torrential’ diuretics?
Loop excretes 15-20% in Na+ in filtrate!
T/F? loop diuretics work on descending limb of loop of Henle?
False. works on ascending limb
What does loop diuretics inhibit?
Na+/K+/2Cl- carriers from lumen into cell
How long do loop diuretics last?
3-6 hours
how long does it take for loop diuretics to onset?
1 hour
Where does loop diuretics act? on the inside of outside of the loop of Henle
outside
3 bad things about loop diuretics?
- hypokalemia
- hypovolemia (elderly)
- metabolic alkalosis
4 scenarios you’d most likely use loop diuretics?
Heart failure
acute pulmonary oedema
ascites (liver cirrhosis)
renal failure
Two kinds of thiazides
True
Thiazide like: indapamide
What diuretics are moderately powerful?
Thiazides
Where and how do Thiazides work?
distal convoluted tubule
knock out Na+/Cl- cotransporter
How long do Thiazides work for?
8-12 hours
What diuretic side effects include gout and hypokalaemia?
Thiazides
Adverse effects of Thiazides?
gout and hypokalaemia
Would you ever combine a loop diuretic and Thiazides?
yes in severe resistant oedema
Which drug has less adverse Thiazides effects?
The thiazide-like drugs: indapamide
example of a K+ sparing diuretics?
spironolactone
are K+ sparing diuretics any good?
by themselves. not really. used in combo with other K+ losing diuretics to counteract hypokalaemia.
What aldosterone receptor antagonist has a slow onset?
Spironolactone
How does spironolactone do its job?
Aldosterone receptor antagonist
Half life of Spironolactone? what lasts longer?
half life of 10 min. metabolite lasts 16 hours
Adverse effects of Spironolactone? 2 things:
hyper kalaemia
GI upset
how would you clinically use Spironolactone?
in combo with loop or thiazides
What diuretic class does triamterene and amiloride belong to? how do they work?
K+ sparing diuretics
block Na+ reabsorption
What’s Mannitol used as pharmacologically?
Osmotic diuretics
3 places Osmotic diuretics effect?
proximal tubules
descending limb
collecting ducts
How do Osmotic diuretics work?
reduce passive water reaboroption
When would you use Osmotic diuretics? 2 things:
raised intra cranial/ocular pressure
prevent acute renal failure
3 compounds that are bad news for kidneys
- heavy metals
- antibiotics
- cancer drugs
kidneys are susceptible to toxicity cause?
- receives 25% of blood supply
- concentration
- reactive species could damage
how does mercury hurt the kidneys?
binds to thiol groups in proteins causes glomerulonephritis
Which antibiotic used to treat gram -ve infections could cause renal toxicity?
Gentamicin via proteinuria, affects apical membrane of proximal tubule, messes with Ca2+ levels which effs up mitochondria
who is more susceptible to gentamicin toxicity?
existing renal disease
Cisplatin treats what and what’s bad about it?
Treats prostate cancer
nephrotoxicity via blood urea increase
proteinuria
electrolyte imbalance
How does Cisplatin mess with the kidney?
activated in cells
binds to thiols
reactive species
