ACS/MI Flashcards
What is a myocardial infarction (MI)?
Ischaemic necrosis to the myocardial tissue.
What is an Acute Coronary Syndrome (ACS)?
Clinical manifestation of myocardial infarction. It is a medical emergency and requires immediate hospital admission.
What are the 3 main types Acute Coronary Syndrome (ACS)?
How are the classified (2)?
- Unstable Angina
- Non-ST Elevated Myocardial Infarction (NSTEMI)
- ST elevated Myocardial Infarction (STEMI)
They are classified by ECG and serial troponin levels.
ECG changes that are indicative of new ischaemia?
- new ST-T changes (e.g. T wave inversion, flat T waves, ST depression)
- new left bundle branch block (WiLLiaM on V1 and V6)
- development of pathological Q waves
CAUTION: sometimes no ECG changes (in unstable angina and NSTEMI)
Non-modifiable risk factors of ACS/atherosclerosis? (5)
- age
- male sex
- FHx of premature CHD
- premature menopause
- certain ethnicities
Modifiable risk factors of ACS/atherosclerosis? (6)
- smoking
- diabetes (impaired glucose tolerance)
- metabolic syndrome
- hypertension
- hyperlipidaemia
- obesity
- physical inactivity
Non-atherosclerotic causes of ACS?
- oxygen supply: oxygen demand mismatch (e.g. lack of supply in anaemia or increased demand in hyperthyroidism)
- coronary emboli (from infected valve)
- coronary occlusion secondary to vasculitis
- cocaine use
- congenital coronary abnormalities
What can an ACS present with? (5)
- epigastric/central chest pain (dull, aching, crushing, pressure, squeezing pain that can radiate to the arms, shoulders, jaw or neck)
- fevers
- chills, clammy
- nausea and vomiting
- limiting daily activities
Atypical presentations of MI are common in (4)
- women
- older men
- diabetic patients
- ethnic minorities
Findings you may see on a cardiovascular examination after an MI?
- low grade fever
- pale, cool, clammy skin
- hypo- OR hypertension (depending on the extent of MI)
- 3rd and 4th heart sounds
- murmurs caused by mitral regurgitation or VSD
- pericardial rub (characteristic of acute pericarditis)
- signs of congestive HF (e.g. raised JVP, peripheral oedema, pulmonary crackles)
What should patients with pre-existing angina be advised to do?
- Take your GTN spray/tablet
- If after 5 minutes the chest pain does not improve, take a 2nd GTN dose
- If after 5 minutes there is still no improvement, take a 3rd GTN dose
- If no improvement after the 3 doses and 15 minutes, call an ambulance immediately.
Cardiovascular differentials for MI (6)
- pericarditis
- myocarditis
- aortic stenosis
- aortic dissection
- PE
- stable angina
Respiratory differentials for MI (2)
- pneumothorax
- pneumonia
Gastrointestinal differentials for MI (5)
- acute gastritis
- GORD
- oesophageal spasms
- cholecystitis
- acute pancreatitis
Main investigations during a suspected MI? (2)
- 12 lead ECG
- Cardiac enzymes (e.g. Troponin I or T)
Other than an ECG and cardiac enzymes (e.g. Troponin), what other investigations are useful in suspected MI? (5)
- Blood tests: FBC, electrolytes, eGFR, lipid profile, CRP, blood glucose
- CXR: for complications such as pulmonary oedema, or to rule out other complications
- Cardiac Magnetic Resonance (CMR): assessing the heart’s function, perfusion and structure
- Coronary angiogram* - GOLD STANDARD for coronary artery disease
- Echocardiogram: check for wall motion abnormalities)
Immediate management of suspected ACS (6)
- urgent hospital admission
- CPR in case of cardiac arrest
- pain relief (GTN, morphine)
- aspirin 300 mg
- resting 12 lead ECG
- supplementary oxygen (aim for 94-98% or 88-92%)
Early management of STEMI (2)
- offer 300mg aspirin loading dose
- medical management OR re-perfusion therapy (Primary PCI or Fibrinolysis)
Early management of NSTEMI/unstable angina (2)
- offer 300mg aspirin loading dose
- GRACE score to determine conservative management (low risk) or immediate angiogram (high risk)
Types of reperfusion therapy in STEMI? (2)
- primary PCI - if presenting before 12 hours of symptoms and procedure can be done within 120 minutes.
- fibrinolytic therapy - thrombolytic drugs if cannot have primary PCI (e.g. streptokinase or alteplase)
When is primary PCI not indicated?
If patient presents after 12 hours of symptom onset and the procedure cannot be done within 120 minutes.
What is the drug therapy for PCI?
When patients undergo Primary PCI, they are offered Prasugrel with aspirin. If there is an increased bleeding risk, Ticagrelor or Clopidogrel should be considered instead.
What is the medical management for ACI? (2 options)
TIP: depends on the bleeding risk
Low bleeding risk: Ticagrelor with aspirin
High bleeding risk: Clopidogrel with aspirin
What is fibrinolysis?
For those patients who cannot be offered Primary PCI, a thrombolytic drug (e.g. Streptokinase or Alteplase) should be given along with an antithrombin (e.g. Unfractioned Heparin, LMWH or Fondaparinux)
When is CABG indicated?
- When PCI has failed
- Occlusion not amenable for PCI
- Refractive symptoms agter PCI
- Cardiogenic shock/mechanical complications (e.g. mitral regurg, VSD)
- multivessel disease (may need to treat the infarct related vessel)
If a patient has a predicted mortality after 6 months of MORE THAN 3% according to the GRACE score, what should the management plan be?
Immediate angiogram and consider primary PCI. Offer Prasugrel/Aspirin or Ticagrelor/Aspirin and a drug-eluting stent.
If a patient has a predicted mortality after 6 months of LESS THAN 3% according to the GRACE score, what should the management plan be?
Conservative management: treat with Ticagrelor and Aspirin (high bleeding risk) or Clopidogrel and Aspirin (low bleeding risk)
Other than primary PCI and fibrinolytic therapy, what other initial management should be considered?
A - ACE inhibitor
B - Beta Blockers
C - Cholesterol-lowering agents (Statins)
D - Dual antiplatelet therapy
E - Eplenerone (an aldosterone antagonist if they have a reduced ejection fraction (<40%) and either Diabetes or clinical signs of HF).
Which patients receive Eplenerone?
The aldosterone antagonist is given when the patient has a reduced ejection fraction (<40%) with Diabetes or clinical signs of HF.
What are the main components of secondary prevention? (2)
- cardiac rehabilitation - lifestyle changes, stress management, health education, physical activity
- drug therapy - ABCDE
What is involved in cardiac rehabilitation following an MI? (4)
- lifestyle advice (driving, sex, flying)
- stress management
- physical activity
- health education/lifestyle changes (healthy eating/Mediterranean diet, low risk drinking, no smoking, healthy weight management)
How any people survive after an MI?
7 in 10 people
What affects prognosis after an MI? (8)
- rise in troponin levels
- degree and extent of changes in the ECG
- degree of LV dysfunction on echocardiogram
- timing and nature of intervention
- co-morbidities
- site of infarction
- depression
- older age and females
Complications following an MI? (5)
D - death
R - rupture of heart muscle or papillary muscles
E - edema (heart failure)
A - aneurysm, arrhythmia (AV node block, ventricular and supra-ventricular arrythmia)
D - Dressler’s syndrome (post-MI syndrome)/pericarditis
