Introduction to Cardiovascular drugs

heart failure drugs that prevent death for 5 years

antiplatelet agents - first drugs used e.g aspirin

reduces activity of platelets to crosslink and form thrombus

cyclooxygenase pathway

•Converts Arachidonic vasoactive and inflammatory mediators

•COX 1- housekeeping

•COX 2- inducible

•Aspirin irreversible inhibitor of COX1 and 2

enzyme that converts fatty acids to prostaglandins-maintain vascular tone and other mediators?

involved in secretion of mucous

involved in inflammation

antiplatelets are secondary prevention drugs

0.25 to 1 % annual risk of significant bleed e.g. haemorrhagic stroke or a bleed that requires blood transfusion and hospital transmission

pharmacokinetic interactions, clopidogrel via cytochrome P450 with omeprazole inhibits digestion, reduces exposure to clopidogrel increasing risk of thrombosis

alpha I receptors on smooth muscle - contraction

Beta I receptors main on the heart - activation leads to tachycardia = increased heart rate, more forceful contraction

Beta 2 receptors on smooth muscle - relaxation

also found peripherally on arteries, leads to dilation of arteries

Sympathetic nervous system response

noradrenaline - main neurotransmitter

adrenaline - stress hormone produced by adrenal medulla

alpha receptors have greater reaction with noradrenaline

beta receptors have greater reaction with adrenaline

Beta blockers : reduce mortality in IHD and heart failure

reduce frequency of symptomatic attacks of angina, AF, and SVT (supraventricular tachycardia)

slowing heart rate down dilates the …

beta blockers 2nd line treatment (4th in hypertension lecture)

beta 1

-bisoprolol

-atenolol

-carvediol

-meoprolol

Beta 1 and 2

-propanolol (anxiety and headache)

calcium channel blockers - block entry into smooth muscle and myocardial tissue

dihydropyridine

-block calcium entry into smooth muscle, causes vasodilatiom

non-dihydropiridine

blocks calcium entry to smooth muscle

-blocks calcium entry in the myocardial pacemaking tissue

RAAS - preserves circulating volume to maintain perfusion of the vital organs

entresto - combination of valsartan and sacubitril inhibits breakdown natriuretic peptides eg ANP and BNP

don’t prescribe ACE inhibitors and entresto, could get angioedmea

antiagnials