Acute Coronary Syndrome

Question 1

what is the pathology of acute coronary syndrome?

Answer 1

• atheromous plaque rupture.
• rarely coronary dissection or coronary spams.
• umbrella term for angina, STEMI and NSTEMI.

Question 2

differentiate between the acute coronary syndromes due to ECG changes and types of myocardial damage.

Answer 2

• ST elevation when full artery occlusion.
• ST depression ischaemia.
• ST and myocardial damage : STEMI.
• ST elevation but no myo-damage : aborted STEMI.
• no ST, Twave inversion and myocardial damage : NSTEMI.
• no ST or damage : unstable angina.

Question 3

differentiate between type 1 and type 2 MI?

Answer 3

• type 1 : atherosclerotic rupture etc leading to thrombotic occlusion and reduction of blood flow causing myocardial necrosis.
• type 2 : non-plaque causes that causes an imbalance between supply and demand. coronary artery spasm, anaemia, respiratory failure, severe hypertension.

Question 4

how would you assess patients suspected of acute coronary syndrome?

Answer 4

• history focused on duration, relieving factors, GTN.
• risk factors.
• haemodynamics to look at BP, heart rate, lungs, heart sounds.
• CXR for pulmonary oedema.

Question 5

what ECG territory changes correspond to what areas on infarct location?

Answer 5

• lateral : lead 1, aVL, V5, V6.
• anteroseptal : V1-V4.
• inferior : lead 2, lead 3, aVF.

Question 6

what abnormalities should you look out for on ECG’s and what do they suggest?

Answer 6

• ST elevation : sudden occlusion.
• ST depression : ischaemia but not sudden occlusion, can sometimes be a posterior STEMI.
• T wave inversion : ischaemic causes but not sudden occlusion.

Question 7

what ECG changes indicate STEMI?

Answer 7

• ST elevation indication PCI.
• hyperacute T waves.
• T inversion.
• pathological Q waves.

Question 8

what changes would you see in NSTEMI?

Answer 8

• ECG : T inversion and ST depression.

- blood : troponins, HBA1C.

Question 9

what is the significance of troponins?

Answer 9

• important in skeletal and cardiac contractility.
• especially T and I sensitive to cardiac origin.
• typically raised within 3h of damage, peaks at 24-48h.

Question 10

why would an echocardiogram be useful?

Answer 10

• see LV function.
• check wall motion.
• valvular disease like mitral regurgitation.
• MI complications.

Question 11

how would you manage a STEMI?

Answer 11

• aspirin.
• 2nd anticoagulant.
• painkillers like morphine.
• nitrates under tongue.
• oxygen in saturation low.
• PCI for stenting.
  TIME IS MUSCLE!!!

Question 12

how would you manage an NSTEMI?

Answer 12

• antiplatelets and antithrombotics : aspirin etc.
• anti-ischaemics : GTN, bisopolol.
• secondary prevention like statins or ACEi.

PCI if ongoing dynamic changes of ECG, develops arrythmias.

Question 13

what is the purpose of an invasive coronary angiogram?

Answer 13

• establishes lesion and location.
• via radial or femoral artery with local anaesthetic.
• stent introduced into now predilated vessel where narrowed.

Question 14

how would you long term manage those with acute coronary syndrome?

Answer 14

• lifestyle changes like low fat diet.
• antiplatelets initially then aspirin for life.
• statin to lower cholesterol.
• Bisoprolol aiming HR 70bpm.
• ACEi to lower BP.