Chronic and Acute Coronary Syndromes

Question 1

What is angina?

Answer 1

Mismatch of oxygen supply and demand on exertion (Type of IHD)

Question 2

What is the most common cause of angina?

Answer 2

Narrowing of coronary arteries due to atherosclerosis

Question 3

What are 5 possible causes of angina?

Answer 3

1) Narrowed coronary artery (Impaired BF)
2) Increased distal resistance (LV hypertrophy)
3) Reduced O2 carrying capacity
4) Coronary Artery
5) Thrombosis

Question 4

What are the M and N-M risk factors?

Answer 4

M: Smoking, Diabetes, Obesity, HTension, High Cholesterol
NM: Family history, gender and Age

Question 5

What is the PP of angina from atherosclerosis and anaemia?

Answer 5

1) AS: Exertion sees increased O2 demand, but CA BF obstructed by plaque –> Ischaemia –> Angina
2) AN: Reduced O2 transport –>Myocardial Ischaemia –> Angina

Question 6

When exercising, what is the compensation for increased myocardial demand?
(Why not possible in CVD?)

Answer 6

Microvascular resistance drops and flow increases as myocardial demand increases
(High epicardial resistance, MVR fall at rest to supply demand at rest, but MVR can’t drop and flow can’t increase to meet demand –> Angina)

Question 7

How is angina reversed?

Answer 7

Resting –> Reduces myocardial demand

Question 8

What are the 5 main symptoms of angina?

Answer 8

1) Crushing central chest pain
2) Relieved pain by GTN spray
3) Provoked pain from physical exertion
4) Pain may radiate to arms, neck or jaw
5) Breathlessness

Question 9

What are main investigations for angina?

Answer 9

1) ECG –> No main markers
2) Echocardiography
3) CT angiography: Good at excluding the disease
4) Exercise Tolerance Test
5) Invasive Angiogram

Question 10

What are the 2 levels of angina prevention?

Answer 10

1) P: Risk factor modification and LD aspirin

2) S: RF mod, Interventional therapy, Pharmacological therapy for symptoms and reduce CV event risk

Question 11

What are 3 symptom relieving pharmacologic therapies?

Answer 11

1) BB: Antagonise symp act. negatively chrono and inotropic (Myocardial work and demand reduced) –> ErecDys tiredness and Bradycardia
2) Nitrates: Venodilators: V Venous return, V pre-load and V myocardial work/demand
3) Ca2+ Blockers: Arterodilators: V BP, V AL, V MC demand

Question 12

What is revascularisation and 2 tpes?

Answer 12

Restores patients CA and increases BF

1) PCI - Less invasive, convenient, high chance of restenosis
2) CABG - Good prognosis, but invasive and long recovery time

Question 13

What are acute coronary syndromes?

Answer 13

Unstable angina, NSTEMI and STEMI

Question 14

What is the most common and uncommon cause of ACS?

Answer 14

C: Atherosclerotic plaque rupture and arterial thrombosis
UC: Coronary vasospasm, drug abuse and CA dissection

Question 15

What are pathophysiological process of ACS?

Answer 15

1) Atherosclerosis –> Plaque rupture and platelet aggregation
2) Thrombus formation –> Ischaemia –> Infarction
3) Necrosis of cells –> Permanent heart muscle damage

Question 16

What are the 2 types of MI?

Answer 16

T1: Spontaneous MI with ischaemia from plaque rupture
T2: MI secondary to ischaemia from increased O2 demand

Question 17

Why does NSTEMI/STEMI see an increase in serum troponin?

Answer 17

Occluding thrombus leads to necrosis of cells and myocardial damage
- Sensitive marker for cardiac muscle injury and significantly raised in reflection

Question 18

What are the 3 main signs of angina?

Answer 18

1) Cardiac chest pain at rest
2) No sig rise in troponin
3) Cardiac chest pain with cresc. patterns (^ frequency and provoking)

Question 19

What are the S/S and complications of MI?

Answer 19

S/S: Unremitting severe central cardiac chest pain, pain at rest, sweating, breathlessness, nausea/vomiting, in bed at night
C: HF, rupture of infarcted vent, rupture of IVS, mitral regurgitation, arrhythmia, heart block and pericarditis

Question 20

What investigations would be done for ACS?

Answer 20

1) ECG
2) Blood test -> Serum troponin
3) Coronary Angiography
4) Cardiac monitoring for arrhythmia

Question 21

What will the ECG of each ACS look like?

Answer 21

STEMI: ST elevation in anterolateral leads, T waves invert, deep/broad pathological Q waves
NSTEMI: Normal/T wave inversion, ST depression, R wave regression (ST elevation and biphasic T wave in lead V3)
UA: Normal/T wave inversion and ST depression (Normal troponin serum)

Question 22

What is the initial management for ACS?

Answer 22

1) Hospital (PCI centre transfer if STEMI)
2) 300mg Aspirin
3) Pain relief
4) Oxygen if hypoxic
5) Nitrates