Ischaemic Heart Disease

Question 1

What is meant by “ischaemic heart disease”?

Answer 1

a lack of blood supply to the heart muscle, which results in chest pain

Question 2

What different conditions are classed as ischaemic heart disease?

What do they all have in common?

Answer 2

IHD encompasses stable angina and acute coronary syndrome (ACS)

• ACS is subdivided into unstable angina, STEMI + NSTEMI

they all involve occlusion of the coronary arteries, but to different extents

in stable angina, the arteries are occluded to a lesser extent

Question 3

How can the different ACS conditions be differentiated from each other?

Answer 3

Troponin blood test:
a negative troponin indicates unstable angina

ECG:
an ECG is performed to look for ST elevation

Question 4

Why does stable angina (angina pectoris) occur?

Under what conditions does it occur?

Answer 4

it occurs when narrowed coronary arteries prevent blood from reaching the myocardium

it occurs PREDICTABLY and with EXERTION (opposite of unstable)

Question 5

What are the risk factors for stable angina?

Answer 5

1. old age
2. smoking
3. hypertension
4. hyperlipidaemia (high LDLs)
5. diabetes

these are the same risk factors for all ACS too

Question 6

What are the symptoms of stable angina?

Answer 6

chest pain that is provoked by exercise / emotions

the chest pain DOES NOT occur at rest

Question 7

What investigations are performed for stable angina?

Answer 7

Resting ECG:
to rule out ACS and any other ECG changes

Lipid profile / HbA1c:
to look for diabetes - another RF

Question 8

What ECG change can sometimes be seen in stable angina?

Answer 8

pathological Q wave

• this indicates a prior infarct (e.g. prev MI)
• it is not necessarily indicative of stable angina

Question 9

What is involved in the management of stable angina?

Answer 9

First line:
* antiplatelet (aspirin 75mg / clopidogrel) + statin

Additional:
* sublingual GTN spray
* beta-blocker / CCB

Question 10

How should a patient be instructed on the use of GTN spray?

Answer 10

• use immediately before any planned exercise / exertion
• SEs include flushing, headache + lightheadedness
• sit down or hold on to something if feeling light-headed
• repeat the dose after 5 mins if pain persists
• if pain has not gone 5 mins after second dose, call an ambulance

Question 11

What drugs may be given to someone with stable angina and why?

Answer 11

aspirin 75mg:
this is first line taking into account risk of bleeding / comorbidities

ACEi:
for people with stable angina + diabetes

statin

Question 12

How does unstable angina differ to stable angina?

Answer 12

this involves chest pain that occurs unpredictably and at rest

Question 13

What investigations are performed for unstable angina?

Answer 13

ECG:
to rule out NSTEMI - should have no changes

Troponin:
this should be negative

CXR:
to rule out other causes of chest pain (e.g. aortic dissection)

FBC:
to assess for thrombocytopenia / bleeding risk prior to treatment

following ix - GRACE score should be calculated

Question 14

What is the first line management for unstable angina?

Answer 14

300mg loading dose of aspirin immediately with an antithrombin (Fondaparinux)

following management depends on the GRACE score

the aspirin is continued indefinitely following the loading dose

Question 15

What parameters are used for the GRACE score?

When is someone deemed to be high risk?

Answer 15

• age
• history of MI / CHF
• resting HR
• systolic BP
• initial serum creatinine
• elevated cardiac enzymes

6-month estimated mortality of >3% is deemed high risk

Question 16

What is the treatment for unstable angina if someone is deemed low risk from the GRACE score?

Answer 16

treatment with ticagrelor + aspirin

if they have a bleeding risk (e.g. low platelets) then aspirin + clopidogrel

low risk = 6-month mortality < 3%

Question 17

What is the treatment for unstable angina if someone is deemed intermediate / high risk from the GRACE score?

Answer 17

• angiography is performed to look at the coronary arteries
• a PCI may be performed if there is NO bleeding risk
• ticagrelor + aspirin is given
• if they are having a PCI, prasugrel is given instead of ticagrelor + aspirin

Question 18

What is an NSTEMI?

What investigations are performed?

Answer 18

non-ST-elevation myocardial infarction

• ECG
• troponin - this will be POSITIVE
• CXR
• FBC
• calculate GRACE score

there is partial occlusion of a coronary artery

Question 19

What ECG changes are associated with NSTEMI?

Answer 19

• T wave inversion
• ST depression

Question 20

What is the first line management for NSTEMI?

Answer 20

• 300mg loading dose of aspirin (continued indefinitely)
• antithrombin (Fondaparinux)

Question 21

What is the management for NSTEMI depending on the GRACE score?

Answer 21

Low risk (< 3%):
* ticagrelor + aspirin
* if there is a bleeding risk, clopidogrel + aspirin

High risk (> 3%):
* angiography +/- follow-up PCI if indicated
* ticagrelor + aspirin
* if PCI is performed, prasugrel is given instead

PCI may be contraindicated if there is comorbidity / active bleeding

Question 22

What are the signs / symptoms of an NSTEMI?

Answer 22

• chest pain that radiates to the jaw, arms + shoulder

in males:
* sweating
* SOB
* nausea

in females:
* sweating
* SOB
* upper back pain

Question 23

What is a STEMI?

What investigations are performed?

Answer 23

ST-elevation myocardial infarction

Investigations:
* ECG
* troponin - will be positive
* coronary angiography if < 12 hours after presentation / gained specialist advice

the coronary artery is TOTALLY occluded

Question 24

What are the signs / symptoms of a STEMI?

Answer 24

• severe central crushing chest pain +/-
• sweating
• SOB
• pallor

it can be SILENT in the elderly / diabetics

Question 25

What ECG changes are associated with STEMI over time?

Answer 25

Initially:
* there are hyperacute T waves (very pointy) followed by ST depression

• this is followed by ST elevation
• ST elevation is dependent on the artery affected
• there may be new onset LBBB

Question 26

How can bundle branch block be recognised?

In which leads are the changes seen?

Answer 26

LBBB - WiLLiam:
* in V1, there is a W shape
* in V6, there is a M shape

RBBB - MaRRow
* in V1, there is an M shape
* in V6, there is a W shape

LBBB can be seen in a STEMI

Question 27

What is the initial first line management for STEMI?

Answer 27

300mg aspirin + continue indefinitely

Question 28

What is the management for STEMI if someone has been having symptoms < 12 hours + PCI is possible within 2 hours?

Answer 28

angiography + PCI

• if patient is NOT taking anticoagulants, prasugrel is given
• if patient is taking anticoagulants, clopidogrel is given

they are also given UFH + antithrombins + drug-eluting stent

angiography allows for visualisation of the position of the clot

Question 29

If someone has had symptoms < 12 hours but PCI is not possible in 2 hours, what is the management for STEMI?

Answer 29

fibrinolysis with alteplast + antithrombin

• they are also given ticagrelor + aspirin
• or clopidogrel + aspirin if bleeding risk is high

ECG is performed 60-90 mins after fibrinolysis

if ST elevation persists, angiography +/- PCI is performed

Question 30

What is the management for STEMI if someone has had symptoms > 12 hours?

Answer 30

• ticagrelor + aspirin if bleeding risk is low
• clopidogrel + aspirin if bleeding risk is high

medical mx only if symptoms > 12 hrs (no PCI)