Manifestation of Myocardial Ischaemia Flashcards Preview

1.2.1. Cardiovascular System > Manifestation of Myocardial Ischaemia > Flashcards

Flashcards in Manifestation of Myocardial Ischaemia Deck (30)
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1
Q

When does coronary artery blood flow occur?

A

Diastole

2
Q

What is a ‘respiratory’ differential diagnosis for a patient with chest pain?

A

Respiratory = pneumonia (temp, cough, breathless), pulmonary embolism (asymptomatic, breathless, sharp/localised pain worse on inspiration).

3
Q

What is a ‘cardiac’ differential diagnosis for a patient with chest pain?

A

Cardiac (muscles/pericardial sac)= ischaemic (dull, retrosternal, central, radiate to jaw/neck/shoulders), pericarditis (sharp, retrosternal, eased with sitting up/leaning forward).

4
Q

What is a ‘GI’ differential diagnosis for a patient with chest pain?

A

GI = reflux (burnin, worse on lying flat/eating).

5
Q

What is a ‘MSK’ differential diagnosis for a patient with chest pain?

A

MSK = rib fracture, costochondritis (sharp, localised, tender, worse with movement)

6
Q

What is the difference between somatic and visceral pain?

A

Somatic = relating to pleural or pericardial (surface) = sharp, localised, worse with inspiration, or positional movement. Visceral = relating to the lung or heart (organ) = dull, poorly localised, worsening with exertion.

7
Q

When does heart tissue ischaemia occur?

A

Only when the metabolic demands of cardiac muscle are greater than what can be delivered via coronary arteries

8
Q

Describe the risk factors for coronary atheroma

A

Male, age, genetics, smoking, hypertension, hypercholesterolaemia, DM, obesity, sedentary lifestyle

9
Q

Describe the pathophysiology of stable angina

A

Coronary artery stenosis = stable atherosclerotic plaque – no rupturing. Spams of coronary artery. Anaemia. Severe aortic valve stenosis.

10
Q

Describe the pathophysiology of unstable angina

A

Atherosclerotic coronary artery disease, ruptures, platelet aggregation, thrombus, acute occlusion

11
Q

Describe the pathophysiology of myocardial infarction

A

Complete/near complete occlusion of coronary artery by ruptured atherosclerotic plaque with thrombus formation

12
Q

What are the clinical features of stable angina?

A

Stable atherosclerosis = at rest level of blood flow is ok, during exercise blow flow can’t reach demand = dull ‘vice’ retrosternal pain, no chest pain at rest, clinical exam often normal, GTN spray relieves pain

13
Q

What are the clinical features of unstable angina?

A

Pain at rest, pain may be more intense, pain may last longer

14
Q

What are the clinical features of myocardial infarction?

A

Dull retrosternal chest pain >15mins, radiate to neck/shoulder/jaw, look unwell, chest pain at rest, increased autonomic output (sweaty, anxious, pallor, nauseous)

15
Q

How is stable angina treated?

A

Aspirin, beta blockers, stain, ACE inhibitors, oral nitrate, nicorandil, CCB, PCI: balloon/stent angioplasty, CABG: coronary artery bypass surgery

16
Q

How is unstable angina treated?

A

Optimise general condition, pharmacological, reperfusion: PCI, CABG

17
Q

How is myocardial infarction treated?

A

Oxygen, pain relief, GTN sublingually, aspirin, reperfusion

18
Q

What characteristic distinguishes unstable angina from stable angina

A

Unstable = pain at rest

19
Q

What is ‘Acute Coronary Syndrome’?

A

Atherosclerotic coronary artery disease, ruptures, platelet aggregation, thrombus, acute occlusion = unstable angina, MI, NSTEMI, STEMI

20
Q

Explain the difference between unstable angina, NSTEMI and STEMI

A

Unstable angina = ischaemia = no enzymes leak. NSTEMI/STEMI = infarct = cardiac enzymes leak

21
Q

Describe the investigations for myocardial infarction

A

ECG, blood tests: troponin

22
Q

Describe the use of the ECG in the diagnosis of MI, distinguishing STEMI from a NSTEMI

A

STEMI = ST elevation, hyperacute T waves. NSTEMI = ST depression, T wave flattening/inversion

23
Q

Describe the use of cardiac biomarkers as a marker for MI

A

Troponin indicates cardiac myocyte death

24
Q

How do biomarkers distinguish between NSTEMI and unstable angina?

A

Troponin release in NSTEMI = infarct tissue death

25
Q

Outline the investigations for stable angina

A

FBC, cholesterol, U+Es, TFT, ECG, chest x-ray (might see cardiomegaly), test for ischaemia = treadmill test, dobutamine stress test

26
Q

What surgical treatments can be used in coronary artery disease?

A

PCI (percutaneous coronary intervention) balloon/stent angioplasty

CABG: coronary artery bypass surgery

27
Q

Describe the signs and symptoms of acute pericarditis

A

More common in men, sharp central retrosternal pain, pain worse on inspiration/lying flat, eased with sitting up and leaning forward, ausculatation = course sounding (pericardial rub)

28
Q

Other than MI, in what cardiac conditions is troponin released?

A

severe stenosis,

myocarditis,

prolonged tachycardia,

defibrillation by CPR,

aortic dissection,

acute heart failure

29
Q

In what non-cardiac conditions is troponin released?

A

Acute PE, pulmonary hypertension, haemodynamic challenge, sepsis, COPD, severe anaemia, polymyositis, seizures, kidney failure

30
Q

How does ischaemia present on ECG?

A

ST segment depression, flat T waves