Ischaemic Heart Disease Flashcards
What is ischaemia?
- inadequate blood flow and oxygen supply to maintain metabolism
What is cardiac ischaemia?
- inadequate blood flow and oxygen supply to the heart muscle
- Synonymous with ‘Coronary artery disease’
Where is predominantly affected in the heart by ischaemia?
- coronary arteries
- sometime caused by exertion
What is atherosclerosis?
- build up of plaque in the arteries
- made up of fat, cholesterol, calcium, and other substances found in the blood
Ischaemic heart disease is made up of a group clinical syndromes that occur due atherosclerosis. What are the 3 most common clinical syndromes of ischaemic heart disease?
1 - angina
2 - myocardiac infarction
3 - heart failure
- arrthymias and mitral valve dysfunction not as common
What does incidence and prevelance mean?
- incidence = new case of a disease (ACUTE)
- prevelance = number of people living with disease (CHRONIC)
How can incidence and prevelance be applied to ischaemic heart disease (IHD)?
- IHD is a chronic condition (prevelence)
- IHD presents with acute symptoms (incidence)
What is the leading cause of mortality, if you do not include cancer?
- ischaemic heart disease
Roughly how many people a year die from ischaemic heart disease?
- 64,000 people
- mean more likely
- associated with deprivation
Incidence and prevelence of ischaemic heart disease both increase with age, but why does the prevelence decrease around the 90s?
- patients die, so appears prevelence decreases
What is angina?
- chest pain caused by reduced blood flow to the heart
What are the common description of patients pain in angina?
- dull
- tight
- squeezing pain
- heavy
In angina is pain localised well?
- no
- felt across the chest
- felt in arms (left), neck and jaw
When are 3 common day to day activities can mean that angina is more likley to occur?
- upon exertion (increased demand on cardiac tissue)
- cold temperatures (blood vessels vasoconstrict)
- following a meal (blood diverted to GIT)
Why is angina described as demand ischemia?
- generally occurs due to increased demand
- reduced blood can flow so when demand increases pain is felt
What is the difference between angina and myocardial infarction?
- angina = narrowing of arteries
- myocardial infarction = complete blockage of arteries
What is visceral pain, also described as referred?
- pain caused by inner organs of the body
- cardiac pain is visceral pain
What aspects of the nervous system and spine does cardiac pain come from?
- autonomic (sympathetic and para-sympathetic)
- generally carried by afferent nerves
- T1-5
- C5-6
- C7-8
What is a myocardial infarction?
- complete blockage of artery
In a myocardial infarction, what pain do patients experience?
- severe and persistent chest pain
- does not go away
- referred and poorly localised
In a myocardial infarction, in addition to pain what are other tell tail signs patients can experience?
- nausea
- fever
- breathlessness
- malaise (general feeling of discomfort)
Is a myocardial infarction caused by increased demand of blood?
- no
- it is just a complete block
What generally causes a myocardial infaction that has been in the arteries for some time?
- atherosclerotic plaque has ruptured
- generally the fibrous cap ruptures
- thrombotic contents initiate blood clot that blocks artery
Once a fibrous cap becomes a vulnerable plaque it is highly likley to rupture. What leaks out of the plaque that is highly thrombogenic?
- collagen triggers platelet activation forming a blood clot
- lipids