Ischaemic Heart Disease Flashcards
What is angina?
Chest pain caused by reduced blood flow to the heart muscle.
What is myocardial infarction?
Heart attack, normally caused by the blockage of one or more coronary arteries.
What is the difference between angina and myocardial infarction
ANGINA - caused by partial blockage
MYOCARDIAL INFARCTION - caused by complete occlusion
What causes pain in a heart attack? PART 1
- Reduced perfusion
- By-products of metabolism (such as CO2) aren’t removed quickly and they activate sensory neurones.
What causes pain in a heart attack? PART 2
- These neurones converge at the same area as the nerves affecting the chest and arm, meaning that those are affected as well. Causes ‘referred pain’.
Compare resistance within the arterioles in a normal heart and during exercise.
NORMALLY - resistance is high
DURING EXERCISE - resistance reduced due to vasodilation
What will happen to coronary arteries when an atheroma develops? How may the heart respond?
- Stenosis in the large coronary artery, increasing the resistance to blood flow.
- Metabolic hyperaemia occurs at rest - blood flow is altered so that oxygen demands can be met in reasonable timeframes
What is exercise intolerance?
Decreased ability to perform physical activity
What are the major risk factors for ischaemic heart disease?
- Smoking
- Age
- Genetics
- Obesity
- Hypertension
- Hypercholesterolemia
What drugs can be prescribed to combat angina?
- NITRATES: vasodilators
- CALCIUM-BLOCKERS: both vasodilators and cardiac depressants
- STATINS - reduce blood pressure
- BETA BLOCKERS - cardiac depressant
What causes exercise intolerance?
- Stenosis has formed in coronary arteries
- Arterioles will dilate during exercise
- Still significantly large resistance to blood flow ∴ oxygen demands cannot be met efficiently
