Cardiovascular formulary Flashcards
(22 cards)
Amiodarone - Indications
Arrhymthias
e.g.. Atrial Fibrillation (AF), Supraventricular tachycardia (SVT), Ventricular tachycardia (VT)
Cardiac arrest - administered after third shock when patient is in VF
Amiodarone - Mechanisms of action
Blockage of sodium, calcium and potassium channels
Antagonism of α and β adrenergic receptors
Reduces spontaneous depolarisation (automaticity), slows conduction velocity, and increases resistance to depolarisation (refractoriness)
Amiodarone - Important adverse effects
Has a long half life and structural similarities to thyroid hormone.
Acute - can cause hypotension during IV infusion
Chronic - Bradycardia, AV block, hypo- or hyperthyroidism, pneumonitis, hepatitis, photosensitivity and grey skin discolouration
Amiodarone - Contraindications
Avoid in patients with:
Severe hypotension,
Heart block,
Active thyroid disease
Amiodarone - Important interactions
Amiodarone Increases plasma concentrations of digoxin, diltiazem and verapamil
Increases risk of bradycardia, AV block and heart failure
ACE inhibitors - Indications
Hypertension - first or second line
Chronic heart failure- first line
Ischaemic heart disease
Diabetic nephropathy and CKD with proteinuria
ACE inhibitors - Mechanism of action
Angiotensin II is a vasoconstrictor and stimulates aldosterone secretion. Inhibition of angiotensin converting enzyme prevents conversion of angiotensin I to angiotensin II
This reduces peripheral vascular resistance (afterload), lowering BP.
Dilation of the efferent glomerular arterioles reduces interglomerular pressure and slows progression of CKD
Reduction of aldosterone level promotes sodium and water secretion, reducing venous return (preload), which helps heart failure.
ACE inhibitors - Importants adverse effects
Common - profound ‘hypotension’ after first dose
‘persistent dry cough’
‘hyperkalaemia’ (because low aldosterone promotes potassium retention)
Can cause or worsen renal failure, particularly in those with renal artery stenosis as they rely on constriction of the efferent glomerular arteriole to maintain filtration.
Rare - angioedema (particularly in blacks) and anaphylactiod reaction
ACE inhibitors - Contraindications
X renal artery stenosis
X acute kidney injury
Avoid in woman who could become ‘pregnant’ and/or are ‘breast feeding’
ACE inhibitors - important interactions
Due to risk of hyperkalaemia, avoid with other ‘potassium-elevating drugs’
ACE inhibitors - Things to communicate
Explain what the treatment is for
Advise about common side effects such as dry cough and dizziness, particularly after the first dose
Mention the possibility of severe allergic reaction
Mae sure they understand the need for blood test monitoring to assess kidney function and potassium levels
Advise to avoid NSAIDS due to risk of kidney damage
ARBs - Indications
Hypertension - first or second line
Chronic heart failure- first line
Ischaemic heart disease
Diabetic nephropathy and CKD with proteinuria
ARBs - Mechanisms of action.
Angiotensin II is a vasoconstrictor and stimulates aldosterone secretion. Angiotensin receptor blockers block the action of angiotensin II on the AT1 receptor.
This reduces peripheral vascular resistance (afterload), lowering BP.
Dilation of the efferent glomerular arterioles reduces interglomerular pressure and slows progression of CKD
Reduction of aldosterone level promotes sodium and water secretion, reducing venous return (preload), which helps heart failure.
ARBs - Important adverse effects
Hypotension (particularly after first dose)
Hyperkalaemia
Renal failure
Unlike ACE inhibitors they do not cause a dry cough as bradykinin metabolism is unaffected
ARBs - Contraindications
X Renal artery stenosis
X Acute Kidney Injury
Avoid in woman who could become pregnant and/or are breast feeding
ARBs - Interactions
Due to risk of hyperkalaemia, avoid ARBs with other ‘potassium-elevating’ drugs
Aspirin - Indications
Treatment for Acute coronary syndrome and acute ischaemic stroke
Secondary prevention of thrombotic arterial events in patients with cardiovascular, cerebrovascular ad peripheral material disease
Used in AF when warfarin in contraindicated
Control of mild to moderate pain and fever
Aspirin - Mechanisms of action
acetylsalicylic acid irreversibly inhibits cyclooxyrgenase (COX) enzyme, reducing the production of thromboxane from arachidonic acid, reducing platelet aggregation.
Aspirin - Adverse effects
Gastrointestinal irritation
Gastrointestinal ulceration and haemorrhage
Bronchospasm due to hypersensitivity reactions
Tinnitus when taken in regular high doses
Overdose is life threatening
Aspirin - Contraindications
X Children under 16yrs old due to risk of Reye’s syndrome (rapid encephalopathy shortly after viral illness + aspirin)
X aspirin hypersensitivity
X Third Trimester of Pregnancy - prostaglandin inhibition may lead to premature closure of ductus arteriosus
Use with caution in people with:
Peptic ulceration - prescribe gastroprotection
Gout - aspirin may trigger an acute attack
Aspirin - Interactions
Use with caution alongside other anti platelet and anticoagulant drugs due to synergistic effects
How should aspirin be prescribed for each indication? include the dose
Acute coronary syndrome - once only 300mg loading dose followed by 75mg daily
Acute ischaemic stroke - 300mg daily for 2 weeks before switching to 75mg daily
Long term prevention of thrombosis is 75mg daily, and should be taken after food, for patients at risk of gastro complications consider 20mg omeprazole daily
Pain relief = 4g max per day
