Acute coronary syndrome (ACS)

Question 1

1) What is ACS usually caused by?
2) What are the 3 types of ACS?

Answer 1

1) Rupture of an atherosclerotic plaque, leading to the formation of a thrombus which blocks a coronary artery
2) Unstable angina, ST elevation myocardial infarction (STEMI) and a non-ST elevation myocardial infarction (NSTEMI)

Question 2

1) Which 4 parts of the heart is supplied by the right coronary artery?
2) What are the 2 branches of the left coronary artery?
3) Which of these branches supplies the left atrium and the posterior aspect of the left ventricle?
4) Which of these branches supplies the anterior aspect of the left ventricle and the anterior aspect of the septum?

Answer 2

1) Right atrium, right ventricle, inferior of the left ventricle and posterior septal area
2) Circumflex artery and the left anterior descending artery
3) Circumflex artery
4) Left anterior descending artery

Question 3

1) What is a type 1 MI?
2) What is a type 2 MI?
3) What is a type 3 MI?
4) What is a type 4 MI?

Answer 3

1) Traditional MI due to a coronary event
2) Ischaemia secondary to increased demand or reduced supply of oxygen i.e. severe anaemia
3) Sudden cardiac death or cardiac arrest suggestive of an ischaemic event
4) MI associated with a PCI/CABG/coronary stunting

Question 4

1) What is the main symptom associated with ACS?
2) Name 2 features/symptoms that are associated with the main symptom?
3) What group of patients may not experience typical chest pain during an ACS?
4) What is this called?

Answer 4

1) Central, constricting chest pain
2) Shortness of breath, nausea and vomiting, sweating and claminess, palpitations, radiating pain to the jaw and arm
3) Diabetic patients
4) Silent MI

Question 5

1) What are the 2 ECG changes that may be seen in a STEMI?
2) What are the 3 ECG changes that may be seen in a NSTEMI?

Answer 5

1) ST segment elevation in the leads consistent with the area of ischaemia and a new LBBB
2) ST segment depression, deep T wave inversion and pathological Q waves

Question 6

What are the 3 aspects needed for a diagnosis of a STEMI?

Answer 6

• ST elevation of >2mm in adjacent chest leads
• ST elevation of >1mm in adjacent limb leads
• New LBBB with chest pain or MI suspicion

Question 7

1) A rise in what protein is consistent with myocardial ischaemia?
2) Name 2 other causes of a raised troponin

Answer 7

1) Troponin
2) Chronic renal failure, myocarditis, pulmonary embolism, sepsis and aortic dissection

Question 8

For the initial management of both STEMI and NSTEMI, what drug is given first, and what dose?

Answer 8

Aspirin 300mg

Question 9

Early STEMI management
1) If available within 12 hrs of presentation, and can be offered within 2 hrs, what is the treatment for an acute STEMI?
2) If this treatment is not available in 2 hrs, within 12hrs of presentation, how is an acute STEMI treated?
3) Give an example of these drugs, and what is their mechanisms of action?
4) Name another aspect of the early STEMI management

Answer 9

1) PCI - percutaneous coronary intervention
2) Thrombolysis with fibrinolytic medication that dissolves clots
3) Streptokinase, alteplase and tenecteplase. They’re tissue plasminogen activators (TPAs) - they activate the conversion of plasminogen to plasmin, which is an enzyme responsible for breaking down clots (thrombolysis)
4) Medical management with ticagrelor (alongside aspirin), cardiology assessment and assess LV function

Question 10

Early NSTEMI management
1) What medications is given in the early NSTEMI management?
2) The early management of NSTEMI is based on what score, and how does this score differentiate intermediate or low and high risk?
3) If there’s intermediate or high risk, what is done?
4) After NSTEMI management, what should be assessed?

Answer 10

1) Aspirin + anticoagulant fondaparinux
2) GRACE score - intermediate or high risk = predicted 6 month mortality >3%. Low risk = predicted 6 month mortality <3%
3) Angiography within 72 hrs
4) LV function

Question 11

After STEMI and NSTEMI early management, what are the next 2 aspects of management?

Answer 11

• Cardiac rehabilitation
• Secondary prevention

Question 12

Cardiac rehab and secondary prevention
1) Lifestyle advice is one component of the cardiac rehabilitation programme (CRP). Name 2 lifestyle advice given and 1 other aspect of the (CRP)
2) What are the 5 drugs given as secondary prevention?

Answer 12

1) Lifestyle advice: reach + maintain healthy weight, healthy diet (Mediterranean), smoking cessation, low risk drinking, regular physical activity (to point of slight breathlessness). Other aspects of CRP = health education, physical activity, stress management
2) ACEi, beta blocker (CCB i.e. verapamil or diltiazem if BB contraindicated), dual antiplatelet therapy (aspirin + clopidogrel), statin

Question 13

Name 3 complications of an MI

Answer 13

• Cardiac arrest
• Cardiogenic shock
• Chronic heart failure
• Tachyarrhythmias or bradyarrhythmias,
• Pericarditis and dressler’s syndrome
• LV aneurysm
• LV free wall rupture
• Ventricular septal defect
• Acute mitral regurgitation

Question 14

1) According to the Killip class, what is the worst prognostic indicator in ACS, and how would this present?
2) For this prognostic indicator, what is the 30 day mortality percentage?

Answer 14

1) Cardiogenic shock - low BP
2) 81%

Question 15

According to the DVLA, a person that’s had an acute MI and a successful angioplasty should be advised from driving for how long?

Answer 15

1 week

Question 16

1) What is Dressler’s syndrome?
2) Name 2 features of Dressler’s syndrome

Answer 16

1) Post-MI syndrome that occurs 2-3 weeks after an MI due to a localised immune response which causes pericarditis
2) Pleuritic chest pain, low grade fever and pericardial rub on auscultation, pericardial effusion, raised ESR

Question 17

Which 2 post-MI complications present similarly with a pan-systolic murmur, and how can they be differentiated?

Answer 17

Acute mitral regurgitation and ventricular septal defect. Acute MR can be excluded with echo

Question 18

A left ventricular free wall rupture post-MI would present with features of what?

Answer 18

Cardiac tamponade

Question 19

What 2 features is a LV aneurysm post MI associated with?

Answer 19

• ST elevation
• Left ventricular failure

Question 20

AV blocks/bradyarrhythmias are most commonly associated with an MI affecting which part of the heart?

Answer 20

Inferior infarct

Question 21

What is the commonest cause of death post-MI?

Answer 21

Patient going into ventricular fibrillation

Question 22

What biomarker is most useful for detecting re-infarcts?

Answer 22

Creatine kinase MB