SIHD and Angina - Therapy Flashcards
Here are the learning outcomes
What are the acute coronary syndromes and the stable coronary artery diseases?
Acute:
Myocardial infarction (STEMI/NSTEMI)
Unstable angina pectoris
Stable:
Angina pectoris
Silent ischaemia
How does SCAD (stable coronary artery disease) arise?
•mismatch between myocardial blood/ oxygen supply and demand
What causes the onset of ischaemia in demand ischaemia vs Supply ischaemia?
What are the determinants of demand?
Heart rate
Systolic blood pressure
Myocardial wall stress
Myocardial contractility
What are the seterminants of supply?
Coronary artery diameter and tone
Collateral Blood flow
Perfusion pressure
Hear rate (duration of distole)
What does hyperlipidaemia result in the deposition of?
Cholesterol esters
Where is the accumulation of foam cells in atherosclerosis?
Subendothelial
What is the cause of disease in atherosclerosis?
Fibrous plaques that project into the arterial lumen reducing blood flow
How can drugs overcome the deman/suppply imbalance?
What is the purpose of drug treatment in stable coronary artery disease?
To releive symptoms
Halt the disease process
Regression of the disease process
Prevent myocardial infarction
Prevent death
Here is a summary of all the potental drug therapies for stable coronary artery disease
From summary of drugs for stable ischaemic heart disease, what is are the rate limiting drugs?
Beta blockers
Ivabradine
Calcium channel blockers
What are the vasodilators used in the treatment of stable ischaemic heart disease?
Calcium channel blockers
Nitrates
Give examples of beta blockers
Bisoprolol and atenolol
What receptors do beta blockers block?
Reversible antagonists of beta 1 and beta 2 receptors
Newer drugs are cardioselective acting on the beta 1 receptors
How do beta blockers serve to decrease demand?
Reduce heart rate, reduce contractility, reduce systolic wall tension, decreases blood pressure, protects cardiomyocytes from oxygen free radicalsf ormed during ischaemic episodes
•Also allow improved perfusion of the subendocardium by increasing diastolic perfusion time
What are the contraindications for beta blockers?
Asthma
Peripheral vascular disease
Raynauds syndrome
Heart failure (those patients who are dependatn on sympathetic drive)
Bradycardia / heart block
What are the adverse drug reactions of beta blockers?
- Tiredness /fatigue
- Lethargy
- Impotence
- Bradycardia
- Bronchospasm
- Rebound –
–Sudden cessation of beta blocker therapy may precipitate myocardial infarction
What are the drug drug interactions of beta blockers?
Hypotentsion when used with other hypotensive agents
Bradycardia when used with other rate limiting drugs such as verapamil or diltiazem
Cardiac failure when used with negatively inotropic agents such as verapamil, disopyramide or diltiazem
NSAIDS antagonise antihypertensive actions
Exaggerate and mask hypoglycaemic actions of insulin or oral hypoglycaemics
How do calcium channels work?
Prevent calcium influx into myocytes and smooth muscle lining arteries and arterioles by blocking the L-Type calcium channel.
Give examples of rate limiting CCB’s and what they do
Diltiazem and verapamil - reduce heart rate and force of contraction - reducing myocardial oxygen requirements