acute coronary syndrome

Question 1

what is acute coronary syndrome (ACS)

Answer 1

it is an umbrella term that includes myocardial infarction with or without ST-segment-elevation (STEMI or NSTEMI), and unstable angina

They are caused by a thrombus (blood clot) caused by a rupture in the artery wall from atheromatous plaque

Question 2

how is ACS diagnosed

Answer 2

a combination of:

• clinical presentations
• ECG
• biochemical cardial markers

Question 3

what is a STEMI

Answer 3

when the arteries are completely and persistently blocked which causes myocardial necrosis (heart muscle dies due to lack of oxygen from no/reduced blood supply)

The ECG shows st-segment ELEVATION

Question 4

what is an NSTEMI or Unstable angina

Answer 4

when the arteries are partially or intemittently blocked. This causes myocardial necrosis (heart muscle death from lack of oxygen due to reduced blood supply) in NSTEMI but not in unstable angina

The ECG shows St-segment DEPRESSION or may be normal

Question 5

what are the differences between NSTEMI and unstable angina

Answer 5

• in NSTEMI myocardial necrosis can occur but it does not in unstable angina
• troponin used to differentiate between NSTEMI or unstable angina

Question 6

what non-drug treatment can be used for ACS (acute coronary syndromes)

Answer 6

can use percutaneous coronary intervention (PCI) or coronary artery bypass graft (CABG) alongside drug treatment

Question 7

what is the initial treatment for all acute coronary syndromes (ACS)

(4 steps)

Answer 7

• pain relief (morphine or diamorphine) + glyceryl trinitrate (sublingual or buccal)
• loading dose of aspirin (300mg) should be given asap (can be given before arriving at hospital)
• monitor patients oxygen saturation. Only give oxygen if it is indicated
• monitor for hyperglycaemia. If blood glucose more than 11 mmol/litre give insulin

Question 8

what is the treatment for STEMI after the initial treatment has occurred

Answer 8

• Coronary reperfusion therapy : either primary percutaneous coronary intervention (PCI )or fibrinolysis (to break down blood clots) should be given as soon as possible. Primary PCI within 12 hours
• add a 2nd antiplatelet (in addition to aspirin) e.g clopidogrel, ticagrelor or prasugrel. Prasugrel is preferred for patients who’ve had primary PCI. if patient has high risk of bleeding, can have aspirin alone
• unfractionated heparin for patients undergoing primary PCI with radial access

Question 9

what is the treatment for NSTEMI or Unstable angina after the initial treatment has occurred

Answer 9

• coronary reperfusion therapy : either primary percutaneous coronary intervention (PCI )or fibrinolysis may or may not occur (depends on patients future CV risk)
• add a 2nd antiplatelet (in addition to aspirin) e.g clopidogrel, ticagrelor or prasugrel. if patient has high risk of bleeding, can have aspirin alone
• offer antithrombin therapy with fondaparinux sodium unless patient is undergoing coronary angiography, or has a high bleeding risk.
• unfractionated heparin should be used as alternative to fondaparinux sodium if patient has significant renal impairment or if they’re undergoing a PCI

Question 10

which patients need secondary prevention of cardiovascular events

Answer 10

all patients who’ve had a STEMI or NSTEMI

Question 11

describe treatment plan for the secondary prevention of cardiovascular events after a patient has had a STEMI or NSTEMI

Answer 11

• start ACE inhibitor (e.g rampiril, enalapril, lisnopril) or ARB (e.g candersartan, valsartan, ibersartan) if ace inhibitor intolerated
• start beta-blocker (e.g bisoprolol, propranolol, atenolol) if patient has had reduced left ventricular ejection fraction (LVEF). if they haven’t, rate-limiting calcium channel blocker verapamil, diltiazem
• continue aspirin (75mg) forever. dual antiplatelet therapy continued for at least 12 months (clopidogrel or ticagrelor. rivaroxaban in patients with raised cardiac biomarkers)
• start a statin
• note these should be started when a patient is hemodynamically stable*

Question 12

what four treatments should be started as part of secondary prevention after a patient has had a STEMI or NSTEMI

Answer 12

start:

• ace inhibitor (or ARB if tolerated)
• beta blocker (or rate-limiting CCB)
• dual antiplatelet therapy
• statin

note these should be started when a patient is hemodynamically stable