MI & Management of Acute Coronary Syndrome Flashcards
(41 cards)
What are the symptoms of myocardial infarction? [8]
- chest pain
- back pain
- jaw pain
- indigestion
- sweatiness, clamminess
- shortness of breath
- none (silent MI) - diabetes/dementia
- death
What are the signs of myocardial infarction? [8]
- Tachycardia (increased heart rate)
- Distressed patient/agitated
- Heart failure (crackles/raised JVP)
- Cardiogenic Shock - due severe ventricular damage
- Hypotensive
- Delirium
- Ventricular Arrhythmia - caused by acute MI
- None
What are the investigations used in acute myocardial infarction? [5]
- Electrocardiograph (ECG)
- Bloods - cardiac troponin
- CXR
- Echocardiogram
- Coronary angiogram
What are you looking for on ECG when investigating acute myocardial infarction? [1]
evidence of ST segment deviation
What are you looking for on CXR and echocardiogram when investigating acute myocardial infarction? [2]
evidence of acute heart failure and left ventricular systolic dysfunction
What is the role of a coronary angiogram when investigating acute MI? [1]
to look at the coronary artery anatomy for any narrowings that need intervention
What is troponin and what are the 3 types? [4]
protein that is an integral part of the cardiac myocyte
3 types:
- TnI
- TnT
- TnC

What is the significance of troponin in the bloodstream?
Presence in the bloodstream = a marker of cardiac necrosis
What is the universal definition of MI? [2]
Any elevation in troponin in clinical setting consistent with myocardial ischaemia
NOTE: isolated troponin elevation does not equal MI
Describe the 6 types of MI [6]
Type 1: Spontaneous MI due to a primary coronary event
- Coronary artery plaque rupture and formation of intraluminal thrombus
- Occludes the coronary artery leading to necrosis of that part of the heart that the artery supplies
Type 2: MI due increased oxygen demand and/or decreased oxygen supply to the heart muscle
- leading to the heart isn’t getting enough oxygen
Type 3: Sudden cardiac death
Type 4a: MI associated with percutaneous coronary intervention
Type 4b: MI stent thrombosis documented by angiography (stent reoccludes causing MI)
Type 5: MI associated with CABG (coronary artery bypass graft)
What conditions can cause Type 2 MI? [6]
- heart failure
- sepsis
- anaemia
- arrhythmias
- hypertension
- hypotension
What are the risk factors for atherosclerotic disease? [6]
- Hypercholesteremia
- Hypertension
- Diabetes mellitus
- Cigarette smoking
- Positive family history
- Obesity (BMI > 30)
What are the non-coronary causes of elevated troponin (type 2 MIs)?
- Congestive heart failure - acute
- Tachy-arrhythmias (i.e. tachycardia)
- Pulmonary embolism
- Sepsis
- Apical ballooning syndrome (Takotsubo cardiomyopathy)
- Anything that stresses the heart (e.g. critically unwell patient)
Define tachy-arrythmias (tachycardia) [1]
Abnormally high heart rate - puts the heart into an increased oxygen demand
Define pulmonary embolism [1]
Blockage of one of the pulmonary arteries in the lungs
What is sepsis and why can it cause elevated troponin? [2]
Life-threatening reaction to an infection
Heart is under a lot of pressure to fight infection
Define apical ballooning syndrome (Takotsubo cardiomyopathy) [1]
Temporary heart condition that is brought on by stress
Has the same symptoms as a heart attack but is not caused by any underlying cardiovascular disease
What are the causes of chronic elevation of troponin (that isn’t an MI)? [3]
Renal failure (troponin is cleared from the blood by the kidneys)
Chronic heart failure
Infiltrative cardiomyopathies (e.g. amyloidosis, hemochromatosis, sarcoidosis)
Define unstable angina [3]
An acute coronary event withOUT a rise in troponin (due to no myocardial necrosis)
i.e. Clinical presentation of an MI + ECG changes
or
Tight narrowing on coronary angiography
Define atherosclerosis [1]
a disease of the arteries in which fatty plaques develop on their inner walls, leading to eventual obstruction of blood flow
Describe the pathophysiology of atherosclerosis [6]
- Dysfunction of the endothelial lining of the vessel leads to inflammation of the vascular wall
- This causes the build up of lipids, cholesterol and inflammatory cells (i.e. cellular debris) within the intima and subintimal layers of the vessel wall
- This results in plaque formation and remodelling of the arterial wall
- At first the body tries to maintain adequate blood flow to the heart muscle by expanding the coronary artery eccentrically → i.e. compensatory expansion maintaining constant lumen
- But over time, the artery cannot expand anymore and the degree of the atherosclerotic plaque begins to impinge on the lumen
- this is when patients present with stable angina
- So under periods of increased demand of oxygen (e.g. exercise), the blood supply is not sufficient to maintain oxygen supply to the heart muscle and the patient presents with symptoms of ischaemia/angina

Define atheroma [1]
degeneration 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 are the risk factors to developing atheroma? [7]
- common in adults in Western countries
- high cholesterol
- smoking
- obesity
- lack of exercise
- diabetes
- hypertension
- family history of early atheroma
Name 1 clinical manifestation that can result from atheroma in…
- kidneys? [1]
- eyes? [1]
- brain? [1]
- heart? [1]
- legs? [1]
- chronic kidney disease (kidney failure)
- visual field defects
- stroke
- angina
- claudication







