ACE Inhibitors Flashcards
What is the mechanism of action of ace inhibitors?
Prevent conversion of AngI to AngII by blocking ACE enzyme, Ang II is responsible for vasoconstriction of renal efferent arteriole and renal mesangium thus causes peripheral vasodilation
Reduces aldosterone and vasopressin release as well as release of nodranline
What are the clinical indications fo ace inhibitors?
Hypertension
Post-MI esp with ventricular dysfunction - prophylaxis as reduces cardiac work and O2 demand as well as remodelling
People high risk of ischaemic heart disease
Heart failure
Diabetic nephropathy (especially Type 1 or with proteinuria/microalbuminuria present) and Progressive renal insufficiency
AF - reduces atrial fibrosis and remodelling, reducing likely hood of stroke
What are ace inhibitors first line for?
1st line for younger Caucasian under 55 or with type 2 diabetes
2nd line for those aged 55 or over and black Africans – more volume expanded as conserve more salt and water + have blunted RAAS system
What are the adverse effects of ace inhibitors?
o Inc bradykinin: dry cough (10-15%) or angioedema (rapid 1st week swelling of lips, tongue, mouth, throat -> air obstruction) <0.2%
o Acute renal failure (renovascular disease e.g. renal artery stenosis, or generalised atherosclerosis, caution in elderly)
ACE inhibitors dilate efferent which reduces glomerular filtration, detrimental if flow is already compromised
Monitor U and E before and after starting or increasing dose
o First dose hypotension in HF or renin levels (esp. if treated with diuretics, sodium/volume depleted or renovascular disease)
o Hyperkalaemia – reduced aldosterone
o Captopril: skin rash and taste disturbance
What are the drug interactions of ace inhibitors?
o Diuretics (hyponatraemia)
o Potassium-sparring diuretics (hyperkalaemia)
o Other hypotensive agents (1st dose hypotension)
o NSAIDS (inhibits prostaglandin, causes constriction of afferent)
Reduce renal blood flow, renal impairment
What are the contraindications of ace inhibitors?
o Low dose in HF (monitor U and E + BP)
o Avoid drug in renovascular disease unless guided by renal physicians
o Look for hyperkalaemia, (avoid supplements or K sparring diuretics)
o Contraindicated in severe aortic stenosis (all vasodilators-> risk hypotension)
o Do not give if pregnancy planned
What are the 1st generation ace inhibitors?
Captopril and Enalapril
Which ones are 2nd generation ace inhibitors?
2nd generation:
lisinopril,
ramipril,
perindopril
trandolapril
Slower onset, longer duration allowing once daily dosing
Less rash/taste disturbance = More commonly used
Which ones are 2nd generation ace inhibitors?
2nd generation:
lisinopril,
ramipril,
perindopril
trandolapril
Slower onset, longer duration allowing once daily dosing
Less rash/taste disturbance = More commonly used
Which ones are 2nd generation ace inhibitors?
2nd generation:
lisinopril,
ramipril,
perindopril
trandolapril
Slower onset, longer duration allowing once daily dosing
Less rash/taste disturbance = More commonly used
