Atherosclerosis : ACS & AMI - Presentation & Investigation Flashcards
What does ACS stand for?
Acute coronary syndrome
What is acute coronary syndrome?
Any sudden event suspected or proven to be related to a problem with the coronary arteries
What is any sudden event suspected or proven to be related to a problem with the coronary arteries called?
Acute coronary syndrome
What is myocardial ischaemia?
Reduction in the blood supply to the heart muscle
What is reduction in the blood supply to the heart muscle called?
Myocardial ischaemia
What is 2?
Right coronary artery
What is 3?
Left anterior descending coronary artery
What is 4?
Circumflex coronary artery
What is 5?
Left coronary artery
What does AMI stand for?
Acute myocardial infarction
What is acute myocardial infarction?
Cell death due to ischaemia
What is cell death due to ischaemia called?
Acute myocardial infarction
What cause of death is heart disease in Scotland?
2nd most common cause of death
What can acute myocardial infarction be due to?
Complete or partial coronary artery occlusion
What is cardiac arrest?
Abnormal heart rhythm that is not compatible with life
What is an abnormal heart rhythm that is not compatible with life called?
Cardiac arrest
What are examples of cardiac arrest?
Ventricular fibrillation or tachycardia
Asystole
What is asystole?
Cardiac flatline so total state of cessation of electrical activity from the heart, more serious form of cardiac arrest and usually irreversible
What is a cardiac flatline, so total state of cessation of electrical activity from the heart called?
Asystole
When can cardiac arrest occur in relation to myocardial infarction?
Can occur during the acute phase or later afterwards
It may also be unrelated to myocardial infarction
What is a ‘heart attack’?
Public use to cover all manner of sudden cardiac onset
What is a word the public use to cover all manner of sudden cardiac events?
Heart attack
What do doctors usually think heart attack means?
Myocardial infarction
What is the process of the evolution of atherosclerosis?
1) Foam cells
2) Fatty streak
3) Intermediate lesion
4) Atheroma
5) Fibrous plaque
6) Complicated lesion/rupture
What is an example of chronic ischaemic heart disease vs examples of acute coronary syndrome?
Chronic ischaemic heart disease - stable angina
Acute coronary syndromes - unstable angina, myocardial infarction (STEMI and NSTEMI)
What is the difference in the blockage of arteries in chronic ischaemic heart disease and acute coronary syndromes?
Chronic ischaemic heart disease (such as stable angina) - less of lumen blocked
Acute coronary syndromes (such as unstable angina then myocardial infarction) - more of lumen blocked
How does complete coronary occlusion affect the ECG initially and after 3 days?
Initially - ST elevation
After 3 days - Q waves
How does partial coronary occlusion affect the ECG initially and after 3 days?
Initially - no ST elevation
After 3 days - no Q waves
How does the thickness of the damage to the heart muscle change for STEMI and NSTEMI?
NSTEMI - only partial thickness damage of the heart muscle
STEMI - full thickness damage of the heart muscle
What is other terminology for STEMI myocardial infarction?
Q wave MI
Transmural MI
What is other terminology for NSTEMI myocardial infarction?
Non Q wave MI
Subendocardial MI
What does the diagnosis of myocardial infarction require?
Detection of cardiac death/injury
and one of:
Symptoms of ischaemia
New ECG changes
Evidence of coronary problem on coronary angiogram or autopsy
Evidence of new cardiac damage on another test
How can cardia death/injury be detected?
Cardiac biomarkers
What are examples of different cardiac biomarkers?
Myoglobin
Troponin
CK-MB
Is more troponin present in STEMI or NSTEMI myocardial infarction?
STEMI
Does troponin increase always mean myocardial infarction?
No, there are many other causes
Other than myocardial infarction, what other things could cause an increase in troponin?
Pulmonary embolism
Cardiac contusion
Anaemia
Sepsis
Renal failure
Sub-arachnoid haemorrhage
What is cardiac contusion?
Bruise of the heart muscle
What is a bruise of the heart muscle called?
Cardiac contusion
What are the different categories of myocardial infarction?
1
2
3
4a
4b
5
What is a type 1 myocardial infarction?
Spontaneous MI associated with ischaemia adn due to primary coronary event
What is a type 2 myocardial infarction?
Due to imbalance in supply and demand of oxygen, not ischaemia due to coronary event
What is a type 3 myocardial infarction?
Sudden cardiac death, with symptoms of ischaemia accompanied by new ST elevation
Verified coronary thrombus after death
What is a type 4a myocardial infarction?
MI associated with percutaneous coronary intervention
What is a type 4b myocardial infarction?
MI associated with verified stent thrombosis via angiography or autopsy
What is a type 5 myocardial infarction?
MI associated with CABG
What could cause a type 1 myocardial infarction?
Coronary atherosclerosis
Coronary vasospasm
Coronary dissection
Embolism of material down coronary artery
Inflammation of coronary artery
Previous radiotherapy to chest causing fibrosis and stenosis of coronary arteries
What could cause a coronary vasospasm?
Cocaine
Triptans
5-FU
Who usually suffers from coronary dissection?
Younger, healthy females
What could cause inflammation of coronary arteries?
Vasculitis
What is seen in the history for acute coronary syndrome?
Chest pain (may radiate to neck/arm)
Nausea
Sweating
Breathlessness
What are some risk factors for acute coronary syndrome?
Male
Age
Known heart disease
Known high blood pressure
High cholesterol
Diabetes
Smoker
Family history
Are males or females more at risk of acute coronary syndrome?
Males
What are some examination findings for acute coronary syndrome?
Look completely fine or very unwell
No specific features to find
Ensure you check heart rate, blood pressure and listen for murmurs and crackles in the chest
What are key investigations for acute coronary syndrome?
ECG
What does an ECG tell you about acute coronary syndrome?
Where the problem is
What are some different locations of myocardial infarction?
Lateral
Anterior
Posterior
Why can posterior myocardial infarctions easily be missed?
No ECG leads on posterior chest
What is a STEMI myocardial infarction caused by?
Completely occluded artery
What does STEMI myocardial infarction cause?
Ongoing myocyte death
What is the treatment for STEMI myocardial infarction?
Get coronary artery open as soon as possible:
Angioplasty (mechanical)
Thrombolysis (pharmacological)
What are some risks of thrombolysis?
Bleeding
Don’t give if recent stroke or ever had a previous intracrainal bleed
Caution if recent surgery, on warfarin, severe hypertension
When should thrombolysis never be given?
If had a recent stroke or ever had a previous intracranial bleed
When does thrombolysis work best?
When given earlier
What is generally the best option for treating STEMI myocardial infarction?
Angioplasty unless cannot get to the lab within 2 hours - then thrombolysis
Compared to STEMI, what do NSTEMI patients tend to be?
Older
More likely to have previous MI
More likely to have other medical problems
What are signs of unstable angina?
Rapidly worsening
Occuring at rest
ECG may be normal or abnormal
No cell death so troponins will not be raised
What is the process of general management for acute coronary syndrome?
1) Admit to hospital
2) Cardiac monitor
3) Give oxygen only if levels are low
What investigations are done for acute coronary syndrome?
ECG (consider doing posterior leads)
Blood tests (check troponin, Hb, kidney function and cholesterol)
What should be check in blood tests for acute coronary syndrome?
Troponin
Haemoglobin
Kidney function
Cholesterol
What is the treatment for acute coronary syndrome?
Glycerol trinitrate (GTN)
Opiates
Anti-thrombotic drugs
Beta blockers
Statin
ACE inhibitors
What does GTN stand for?
Glycerol trinitrate
What effect does glycerol trinitrate (GTN) have?
Vasodilator (opens up coronary arteries)
How can GTN be administered?
Sublingual or IV infusion
What is an example of an opiate?
Morphine
Why are opiates given for acute coronary syndrome?
Relieves anxiety
Helps venodilate
What are the different categories of anti-thrombotic drugs?
Anti-platelet drugs
Anti-coagulant drugs
What are examples of anti-platelet drugs?
Aspirin
Clipidogrel
What are examples of anti-coagulant drugs?
Heparin
Low molecular weight heparin (LMWH)
Fondaparinux
Why are beta blockers used for acute coronary syndrome?
Reduces the work the heart has to do
What do statins do?
Lower cholesterol
Why are ACE inhibitors given for acute coronary syndrome?
Helps the heart muscle recover
Do patients with an NSTEMI myocardial infarction always need a coronary angiogram?
They often do, use common sense
What are some risks of coronary angiography and angioplasty/stenting?
Bleeding
Blood vessel damage
Myocardial infarction
Coronary perforation
Stroke
Dye affecting kidney function (contrast neuropathy)
What does PCI stand for?
Percutaneous coronary intervention
What does CABG stand for?
Coronary artery bypass graft
What surgical options are there for revascularisation?
Percutaneous coronary intervention (PCI)
Coronary artery bypass graft (CABG)
What are some possible complications following myocardial infarction?
Arrhythmia
Mechanical such as myocardial rupture, acute ventricular septal defect and mitral valve dysfunction due to papillary muscle rupture)
What are some possible longer term consequences following myocardial infarction?
High risk of further myocardial infarction/death
Cardiac failure
Risk of bleeding as on anti-platelet drugs
Potential delay in getting other operations when on anti-platelet drugs
