Antianginal Medication Flashcards
What is the symptom of Angina Pectoris?
Tight chest
What is the underlying cause of Angina Pectoris?
Atherosclerosis
What causes Angina Pectoris?
Oxygen supply to the myocardium is insufficient for it’s needs
What can the chest pain be described as in Angina Pectoris?
Intense
Diffuse
Gripping
Constricting
Suffocating chest pain
Hard to distinguish from ‘heart burn’
Where can Angina pectoris pain radiate to?
Arms, Neck and Jaw
What is the lumen of an artery like in someone with Angina Pectoris?
Artery is smaller due to plaque growth.
What causes the artery to be blocked?
Rupturing of the plaque on an artery, platelet activation, thrombus, blood clot, blockage!
What is the aim of treatment for someone with Angina?
*Alleviate acute symptoms
*Minimise frequency of ischaemia
*Reduce progression of atherosclerosis
What secondary prevention measures can be put in place to reduce the progression of atherosclerosis?
Statins
Aspirin
ACEI in diabetes
What can increase a cardiac workload and trigger angina?
Exercise, Emotion, GI perfusion (heavy meals), Peripheral vasoconstriction
What can physically reduce the oxygen supply to the heart causing angina?
*Restricted coronary perfusion
* Narrowing of the coronary arteries (atheroma)
*Limits on dilation
*Aortic stenosis
*Atherosclerosis
How do we reduce the oxygen demand to the heart?
-Reduce perfusion demands
-Reduce pre-load
-Reduce afterload
-Reduce cardiac rate/contractability
-Improve efficiency of the heart
How can we reduce perfusion demands on the heart?
Rest, stress reduction, smoking, weight
How can we reduce the pre-load on your heart?
Venodilator - Nitrates!
How can we reduce afterload on the heart?
Arterial dilator
CCB, Nitrates
How can we reduce cardiac rate/contractilibility and cardiac workload?
Negative iontrope/chronotrope
-B-blocker
-CCB (Amlodipine etc)
How do we improve efficiency of the heart?
Exercise, stop smoking, lifestyle!!
How do we improve oxygen supply to the heart?
Increase coronary flow
Arterial dilator - more relaxed
-CCB
-Nitrates
Surgery - bypass, angioplasty, stent
What are the anti-anginal agents?
-Organic nitrates (acute attacks)
-CCB
-B-adrenoreceptor antagonists (b-blockers)
-Potassium channel activators - vasodilators
Why are b-blockers used for angina?
Slow heart rate so reduce metabolic demand
What are the long acting organic nitrates?
Isosorbide mononitrate
MOA of nitrates?
Nitric oxide is released from organic nitrates , this relaxes smooth muscle, decreasing pre-load.
What do lower doses of nitrates do?
-Marked dilation of large veins
-Reduction in central venous pressure (pre-load reduced)
-Reduction in cardiac output and oxygen consumption
-Little effect on arterioles/little change in BP
What do higher doses/chronic use of nitrates do?
-Arteriolar dilation
-Fall in BP
-Reduced cardiac output
-Headache