Pharmacology of heart failure and hypertension Flashcards
How does pulmonary oedema occur in heart failure?
Left ventricular dysfunction - fluid backs up into pulmonary capillaries - hydrostatic pressure increases - fluid enters lungs
Acute treatment for pulmonary oedema:
Diamorphine O2 Diuretic Nitrates Ventilatory support Inotrophic support
What diuretic is used in pulmonary oedema?
IV furosamide
What is diamorphine used to do in PO?
Relief of anxiety
vasodilation
Nitrates act to
Vasodilate
Types of ventilatory support:
CPAP
IPPV
CPAP
Continuous postive airway pressure
IPPV
Invasive positive pressure ventilation
What can be used as ionotrophic support?
Dobutamine
Dobutamine =
Synthetic catecholamine
Following recover from PO, patient has what?
Chronic heart failure
What should a patient be started on after acute PO?
Diuretic
Beta blocker
ACEi
What is the aim of treatment for anasarca?
Need to induce diuresis
Ways to induce diuresis:
Best rest Fluid restriction Diuretic Inotrophic support Mechanical help: dialysis
What should you give to a patient on bed rest?
LMWH
Diuretics of choice in HF:
Loop
Loop + thiazide
Problems caused by loop diuretics:
Hypokalaemia
Hyponatreaemia
Hypercaemia
MoA amiloride:
Blocks K+/Na+ exchanger
MoA spironolactone
Aldosterone antagonist
1st line treatment for HF:
Diuretics
ACEi (or ARB)
Betablocker
MRAs
ARB =
Angiotensin II receptor blocker
MRAs =
Mineralcorticoid receptor antagonist
Suffix of ARB
-sartan
What is ACE escape?
Angiotensin II can be made by other enzymes
What does ARBs get around?
ACE escape
Why are ACEis better than ARBs
ACE breaks down kinins (vasodilators). Kinins increase
What do ACEi and ARB cause?
Fall in BP
Rise in K+
Rise in creatinine
Fall in Hb
Why does ACEi cause a rise in creatinine?
Renal artery stenosis
Side effects of ACEi
Cough
Rash
Angio-oedema
Why may we need MRAs?
Aldosterone not totally suppressed by ACEi
Name 2 MRAs
Spironolactone
Epleronone
Side effects of spironolactone:
Hyperkalaemia
Gynaecomastia
Name a SARA
Eplerenone
SARA =
Selective aldosterone receptor antagonist
a1 receptors cause
Vasoconstriction
What acts on a1 receptors
Noradrenaline
b1 is found on
Cardiac muscle
Kidneys
b2 is found on
Peripheral vessels
Ciliary body
Bronchodilation
Decrease GI contractility
Is sympathetic activation good or bad in HF?
Bad
Effect of blocking b1 =
Decrease in HR
Decrease contractility
Decrease renin release
Effect of blocking b2 =
Vasoconstriction of vessels Bronchoconstriction Speeds up GI motility Reduce IOP Less glucose released, more glucagon
How to betablockers help in HF?
Improve myocardial function Protect myocytes Slow HR Anti-ischaemia Anti-arrythmic Ejection fraction improves
Examples of non-selective beta blockers
Propanolol
Timolol
Nadolol
Examples of selective beta blockers
Atenolol
Metoprolol
What conditions are selective beta blockers prefered for?
COPD
Asthma
Diabetes
Ivabradine =
Inhibits pacemaker current, slows HR
Aliskiren =
Direct renin inhibitors
What enzymes system blocks ANPs?
NEP
Sacubritil =
NEP inhibitor
Valsartan =
ARBs
Digoxin is indicated in
Atrial fibrilation
Atrial flutter
HF
MoA of digoxin
Blocks Na+/K+ on cardiac myocytes
Ca2+ moves in
4 drugs to avoid in HF
- Calcium antagonists
- Positive inotrophs
- Aspirin
- Statins
ABCD of hypertension:
ACEi
Beta blockers
Ca2+ blockers
Diuretics
MoA of calcium antagonists:
Reduce BP
Negative inotrophy
Name 2 dihydropyridines =
Amlodipine
Nifedipine
Name 2 non-dihydropyridines =
Verapamil
Diltiazem
Doxazosin =
Alpha blocker