Acute coronary syndromes Flashcards
What happens if blood vessels are narrowed? (3 points)
- This causes an inadequate oxygen supply to be delivered to the tissues
- Causes ‘cramp’ in affected tissues/muscles
- There will be no residual deficit at first
What happens if there is blood vessel occlusion? (3 points)
- No oxygen delivery to tissues causing tissue death
- More sever pain than if BV’s are only narrowed
- Loss of function of the tissue
What is ischaemia?
- An inadequate blood supply to an organ or part of the body
What is infarction?
- Tissue death as a consequence of the blockage of arteries
What is key for survival of long term acute coronary syndromes?
- Getting effective treatment early
What does STEMI stand for?
- ST segment elevates myocardial infarction
What is atherosclerosis?
- A disease of the arteries characterised by the deposition of fatty material on their inner walls
What are coronary arteries?
- An artery supplying blood to the heart
What may happen if there is an issue with one of the coronary arteries?
- An issue with one of these arteries is enough to kill you
What is angina pectoris?
- Reversible ischaemia of heart muscle
- Caused by the narrowing of one or more coronary arteries
What is ‘classical’ angina made worse with?
- Exercise
What is unstable angina?
Unstable angina is chest pain that occurs at rest or with exertion or stress. The pain worsens in frequency and severity. Unstable angina means that blockages in the arteries supplying your heart with blood and oxygen have reached a critical level.
How would a patient describe the pain cause by ‘classical’ or ‘unstable’ angina?
- As a central crushing chest pain
- Radiation to the arm, back and jaw is possible
- This type of pain is distressing for the patient
Do you get pain at rest with ‘classical’ angina?
- No
You get pain from ‘classical’ angina with certain levels of exertion. What can make this worse? (2 points)
- Cold weather and emotion
You get pain from ‘classical’ angina with certain levels of exertion. What can this be relieved by?
- Relieved by rest
- Patient lives within limits of tolerance
How quick is the deterioration of people with ‘classical’ angina?
- It is a gradual deterioration
What are the usual signs of ‘classical’ angina? (4 points)
- Often none
Occasionally hyperdynamic circulation:
- Anaemia
- Hyperthyroidism
- Hypovolaemia
What is hypovolaemia?
- A condition in which the volume of blood plasma is too low
What investigations can be carried out do determine if a person has angina? (4 points)
- ECG reading at rest and exercise
- Angiography
- Echocardiography
- Isotope studies (function ass essment)
With ischaemia, what would you see on an ECG?
- Will get ST segment elevation but as it gets worse will get ST segment depression
- If do ECG and put them on a treadmill you will be able to see these changes happening before the patient feels pain
What is a rhythm strip in an ECG?
- Shows the rhythm of the heart over a period of time
- So, shows you how regular the heart is - is there any change in the rhythm over time
One way in which you could treat angina would be to reduce the oxygen demands of the heart. How could you do this? (2 points)
- Reduce the afterload (blood pressure)
- Reduce the preload (venous pressure)
One way in which you could treat angina would be to increase the oxygen delivery to the tissues. How could you do this? (2 points)
- Dilate blocked/narrowed vessels (angioplasty)
- Bypass blocked/narrowed vessels (Coronary Artery Bypass Grafting - CABG)
What is an angioplasty?
- Surgical unblocking of blood vessels
What is Coronary Artery Bypass Grafting (CABG)?
- Taking a blood vessel from another part of the body and attaching it to the coronary artery above and below the narrowed area or blockage
What non-drug therapy’s can be used to reduce the risk of angina? (4 points)
- Live within limitations of what patient can do
Modify risk factors:
- Stop smoking (will improve blood flow to the heart muscle)
- Graded exercise programme (gradually build up exercise)
- Improved diet/control cholesterol
Which drug can be given to reduce the risk of MI?
- Aspirin
What drugs can be used to reduce hypertension? (3 points)
- Diuretics, Ca channel antagonists
- Ace inhibitors, Beta blockers
What drugs can be used to reduce preload/dilate coronary vessels?
- Nitrates - can get short or long acting
What drugs can be used as emergency treatment for angina?
GTN spray/tab
What is GNT spray and what is it used for?
- Glyceryl trinitrate = a spray used to relieve angina (chest pain). When sprayed under the tongue it relaxes and widens blood vessels in the heart and the rest of the body
What is the problem with CABG as surgical therapy for angina?
- The benefit of the surgery is not always obtained
CABG can be used as surgical therapy for angina. It is classed as a major surgery. Why?
- There is a mortality risk
- Have to stop the heart to do it - risky
Using CABG as surgical therapy or angina the patient will get a limited benefit. How long will this last?
- 10 years
- Less in smokers who continue to smoke
In comparison too CABG, how good are angioplasty’s and stenting in terms of risk and benefit?
- Lower risk but lower benefit
- Risk of vessel rupture during procedure
What kind of intervention is angioplasty’s and stenting classed as?
- Percutaneous intervention
What is meant by percutaneous intervention?
- A non-surgical method used to open narrowed arteries that supply the heart muscle
Angioplasty and stenting are lower risk than CABG. However what else is lower?
- The benefit
What is there a risk of when performing an angioplasty or stent?
- Risk of vessel rupture during the procedure
What kind of therapy does the patient need when getting an angioplasty or stent?
- Dual anti-platelet therapy
- Which is the prescri ption of an antiplatelet medication in tandem with a recommendation to take a daily dose of aspirin
What is an angioplasty?
- The use of a balloon to stretch open a narrowed or blocked artery
What is dual antiplatelet therapy?
- Prescription of antiplatelet medication in tandem with a recommendation to take a daily dose of aspirin
What is the name for ‘angina’ of the tissues?
- Peripheral vascular disease
- Usually occurs on the lower limb
What is an atheroma?
- Degradation of the walls of the arteries caused by accumulated fatty deposits and scar tissue, and leading to restriction of the circulation and a risk of thrombosis
What is the cause of peripheral vascular disease in lower limbs?
- Atheroma in the femoral/popliteal vessels
What is a common symptom of peripheral vascular disease?
- ‘claudication’ pain in limb on exercise
- claudication is a condition in which cramping pain in the leg is induced by exercise, typically caused by obstruction of the arteries
- Pain can be relieved with rest
How is peripheral vascular disease managed?
- In the same way as angina
Peripheral vascular disease indicates an ‘arteriopathy’ which is an MI risk. What is an arteriopathy?
- A disease affecting a joint
Peripheral vascular disease may lead to tissue necrosis and gangrene. What can this result in?
- Amputation
What can peripheral vascular disease be aggravated by?
- CV risk factors
How does ischaemia turn to infarction? (5 points)
- Atheroma in vessels de to ulcerated plaques with platelet aggregation
- A thrombosis forms on the surface
- The thrombosis can enlarge rapidly to block the vessel
- Plaque surface/platelets detach from the thrombosis and travel downstream and BLOCK vessels
- No blood flow to the area causes infarction
What causes infarction in the heart?
- Coronary artery atheroma
What causes infarction in the lower limbs?
- Atheroma of the femoral & popliteal arteries
What causes infarction in the brain?
- Atheroma in the carotid arteries
- Junction of the internal and external carotid
What are the 5 different types of myocardial infarction?
- Spontaneous - primary coronary event - plaque fissure/rupture
- MI secondary to ischaemia - balance of supply and demand
- Sudden death with symptoms of ischaemia and evidence of ST elevation or thrombus
- MI from PCI (percutaneous coronary intervention)
- MI from CABG
How can yo reduce the tissue loss from necrosis because of infarction? (5 points)
Open blood flow to ischaemic tissue
- Thrombolysis (within 6 hours)
- Angioplasty (with stent is best possible treatment if you can do it within 3 hours)
Bypass the obstruction
- CABG, Fem/pop bypass
How can you prevent a further episode of infarction ? (2 points)
- Risk factor management
- Aspirin
What medical/surgical emergency procedure could be given to someone with a limb infarction? (2 points)
- Thrombolysis
- Salvage surgery
Limb infarction may result in acute limb necrosis. What is the treatment for this?
- Amputation
What is the name for an infarction of the brain?
- Stroke
What are the 2 types of stroke and why is it important to know which one it is?
- Usually an embolism from atheroma but can occasionally be a cerebral bleed
- Treatment complicated beca use if it is an infarction you are dissolving the clot to relieve the infarction but if it is a bleed then you have a clot preventing the blood from going into the brain and if trat for an infarction you are dissolving the clot so more blood wil go into the brain making it worse
What are transient ischaemic attacks?
- A brief episode of neurological dysfunction resulting from an interruption in the blood supply to the brain, sometimes a precursor to stroke
- PAtient will get all of the symptoms of a stroke
The deficits when someone has a stroke are variable, but usually result in a loss of function. What determines what sort of function is lost?
- Depends on the brain region involved
- Will usually get some recovery with time
What is the treatment of strokes and transient ischaemic attacks?
- Specialist centres - trials
What are the signs and symptoms of MI? (6 points)
- Pain
- Nausea
- Pale
- Sweaty
- ‘going to die’ feeling
- OR sient MI’s (people that have no signs or symptoms)
What can MI’s cause? (2 points)
- Death
- Functional limitation
What could you see in an ECG of a person with a MI? (2 points)
- ST segment elevation/ T wave abnormalities (varies in position with infarct but also may be normal
- Q waves will only indicate an OLD MI
Which cardiac enzymes can you test to investigate possible MI’s? (3 points)
- Troponin (will go up dramatically from onset of pain to full blown MI)
- Creatine Kinase (specific for heart muscle and also for troponin)
- LDH & AST increase - not specific
What primary care would be given for an MI?
- Aim to get patient to hospital as soon as possible
- Analgesia, aspirin and reassurance
- BLS if required
What is analgesia?
- Medicine given for pain
What would be the treatment for an MI once in the hospital? (4 points)
- Primary percutaneous coronary intervention e.g. angioplasty & stenting (if can do within the 3 hour window)
- Thrombolysis if indicated (6 hour window)
- Drug treatment to reduce tissue damage
- Prevent recurrence/complications by secondary prevention
Give an example of medication that would be given to a patient in a hospital who had suffered from an MI?
- Aspirin
Give an example of conditions patients must satisfy in order to be able to have thrombolysis? (8 points)
- Injury/surgery/ IM injections
- Severe hypertension, active PUD (Peptic ulcer disease)
- Diabetic eye disease, liver disease, pregnancy
What are the possible complications of MI? (6 points)
- Death
- Arrhythmias
- Heart failure
- Ventricular hypofunction & thrombosis
- DVT & pulmonary embolism
- Complications of thrombolysis
What medical management can be used to prevent another MI? (4 points)
- Risk modification
- Aspirin
- Beta-blocker (reduces the risk of having an abnormal heart rhythm)
- ACE inhibitor
What do Beta-blockers do?
- Reduce blood pressure and force around the body
What do ACE inhibitors do?
- Prevents the body from creating a hormone called Angiotensin II. They do this by blocking a chemical called angiotensin-converting enzyme. This has a variety of effects but essentially relaxes blood vessels and helps to reduce the amount of water resorbed by the kidneys
What are 3 things that may also need to be treated after a person has had an MI?
- Heart failure
- Arrhythmias
- Psychological distress
