Coronary Artery Disease Flashcards
(8 cards)
P2Y12 Antagonist
(Clopidogrel, prasugrel, ticagrelor)
MOA: The active metabolite of the clopidogrel (thienopyridines) irreversibly bind to the platelet P2Y12 receptor and inhibits platelet aggregation for the life of the platelet.
Indicated: Ischaemic stroke or High risk TIA
Precautions: CYP2C19 poor metabolisers - efficacy of clopidogrel may be decreased consider an alternative antiplatelet drug.
Side effects: Bleeding, skin reaction
Dose: 75mg (1 tablet) once daily)
Time to max effect is 7 days
Counsel:
- Avoid grapefruit juice as it may decrease efficacy of clopidogrel
Antiplatelet
(Aspirin)
MOA: Inhibits platelet aggregation by irreversibly inhibiting COX-1, reducing the synthesis of thromboxane and inducer of platelet aggregation.
Precaution: >75yrs take aspirin have an increased risk of major bleeding
Side effect: GI irritation, increased bleeding time
Dose
- Initial Ischaemic stroke, high risk TIA = 150-300mg once daily
- Long term 75mg - 100mg once daily
Thrombolytic / Fibrinolysis (Rt-PA)
(Alteplase, Tenecteplase)
MOA: Binds to fibrin meshwork and converts plasminogen to plasmin (a protease which converts insoluble fibrin to soluble fibrin degradation product) breaking down the clot
Precaution
- Risk of bleeding
- Tx with ACEI may increase risk of allergic reaction
- Elderly >80 use of alteplase is associated with poorer outcome and risk of intracranial hemorrhage and death
Side effect: bleeding, intracerebral bleeding, itnernal bleeding, transient hypotension
Counsel
- Given within 405hrs of onset of symptoms or local protocol can be given up to 9 hours
Ivabradine
MOA: inhibits a current regulating the interval between depolarisations of the sinoatrial (SA) node. It reduces heart rate (by about 10 beats/minute) which in turn lowers cardiac workload and myocardial oxygen demand
Precautions
- HR <70 beats/min before tx ubstable angina, acute heart failure
- BP <90/50mmHG
- Not used in pregnancy and breastfeeding
- Tx with drugs that inhibit CYP3A4
ADR: bradycardia is dose related, AF, ventricular, dizziness
Counsel
- Vision may be blurred and see bright areas especially sudden changes in light intensity
- Take with food
- Swallow whole
- Avoid grapefruit juice
Dose: initially 5mg bd adjust after 2-4 weeks according to HR (range 2.5-7.5 mg bd
Nicorandil
MOA: Increases cGMP levels resulting in relaxation of the coronary vascular smooth > improve blood flow + decrease preload reducing myocardial oxygen demand
Precaution
- pregnant and breastfeeding
- severe hepatic impairment
ADR: headache, dizziness, lethargy, nausea, flushing
Counselling:
- Tell doctor any ulcer wounds or skin problem that are slow to heal
start at a low dose to reduce risk of ADR
Perhexiline
MOA: It inhibits carnitine palmitoyltransferase, which may change myocyte metabolism from long-chain fatty acids to glucose, leading to improved myocardial oxygen utilisation and anti-ischaemic effects.
ADR: dizziness, headache, weightloss
Precaution:
- diabetes
peripheral neuropathy
treatment with drugs that inhibit CYP2D6
Counsel
- regular blood test is needed
- measure liver function and weight
- Tell doctor of weakness, weight loss, numbness, pins and needle
Dose: 200mg initially, then increase to maintenance 100-250mg daily
Glycoprotein IIb/III3 inhibitors
(Tirofiban and Eptifibatide)
MOA: Prevent binding of fibrinogen to platelet, by occupying glycoprotein IIb/IIIa receptor, thereby blocking platelet aggregation. Tirofiban is a non-peptide antagonist; eptifibatide is a cyclic heptapeptide.
Precaution:
- reduce CrCl: <50mL/min
- Avoid in hepatic
- Risk of bleeding
ADR: bleeding, thromocytopenia
Nitrate
(Glyceryl trinitrate, isosorbide)
MOA: Provide exogenous source of nitric oxide (which mediates vasodilator effects). Predominantly venodilators; reduce venous return and preload to the heart, reducing myocardial oxygen requirement.
ADR: headache, flushing, palpitation, orthostatic hypotension, fainting, peripheral oedema
Contraindicated in hypotension, hypertrophic obstructive cardiomyopathy, hypovolaemia, raised intracranial pressure, anaemia, tx with PDE5 inhibitor
Isosorbide: Initially 30-60mg daily increase 120mg daily
GTN patch : 5mg/24hr daily for 12-14 hrs each day, increase to 15mg/24hrs if needed
GTN sublingual spray: 400-800mcg (1-2 sprays) repeat after 5 minutes if necessary to max of 3 sprays
- prevent: 1 spray 5-10 minutes before activity
GTN sublingual spray
- Prime the spray before using it for the first time by pressing the nozzle 5 times, spraying it into the air. Prime it with 1 spray if it hasn’t been used for 7 days. Prime it with 5 sprays if it hasn’t been used for more than 4 months. Storage is 90 days from opening bottle, keep away from light and heat
Patch
- Apply to clean skin on the chest or upper art, rotate site to avoid skin irritation
- Wear when symptoms of angina are most frequent
- A patch free period of at least 8 hours in each 24hr period
