CVS - IHD

Question 1

causes of IHD

Answer 1

main cause: atherosclerosis
embolism
arteritis
aneurysms

Question 2

IHD pathogenesis

Answer 2

supply does not meet demand

• reduced coronary flow (occlusion of artery)
• increase myocardial demand (pregnancy, hyperthyroidism)
• less oxygen carried in the blood (anemia, L->R shunt)

Question 3

formation of stable and unstable plaques

Answer 3

stable plaque: smaller lipid core, more fibrous tissue

unstable plaque: large lipid core, thin fibrous cap - risk of rupturing and causing plaque haemorrhage (thrombus)

Question 4

clinical manifestations of IHD

- chronic and acute

Answer 4

chronic:

• stable angina
• cardiac failure

acute:

• unstable angina
• myocardial infarction (AMI)
• sudden cardiac death

Question 5

3 types of angina + treatment

Answer 5

SUP

• stable angina: chest pain only on exertion
• unstable angina: worst - increasingly frequent, risk of thrombosis and vasoconstriction + MI
• prinzmental angina: recurrent even at rest, esp at night
  treatment: vasodilators (GTN)

Question 6

myocardial infarction + clinical diagnosis

Answer 6

death of cardiac muscle cell

• mainly regional effects: thrombus formation
• circumferential: hypoperfusion

diagnosis:
- ECG
- crushing chest pain
- elevated cardiac enzymes (like liver: ALT/AST elevated when there is LF)

Question 7

myocardial infarction pathogenesis

Answer 7

- coronary artery occluded
to see which artery is affected: see which leads have ST elevation
- V1-V4: LAD
- V5,V6,I,aVL: left Cx
- II,III,aVF: RCA

• transmural MI: infarction of the full thickness of the myocardium
  ischemia, embolism, vasospasm

Question 8

myocardial infarction morphology**

Answer 8

9-12hrs - macroscopically/microscopically not visible
12-24hrs - macro: pale with blotchy discolouration;
micro: eosinophilic, loss of nucleus, intercellular edema

1-3 days - macro: yellow; micro: neutrophil infiltration
3-10 days - macro: hyperaemic around yellow parts; micro: granulation
>days - fibrous scar

Question 9

myocardial infarction complications

Answer 9

- ventricles: 
myocardium rupture -> cardiac tamponade (fluid fill the peritoneum so heart cannot fully expand)
LV failure -> congestive HF
- conduction: arrhythmia
- infection: pericarditis 
- valves: rupture of papillary muscle

Question 10

cardiac death pathogenesis

Answer 10

arrhythmia from ventricular fib

caused by stenosis of the arteries/ acute plaque changes so decrease blood supply

Question 11

complications of AMI (6)

Answer 11

PAIRAT

• arrhythmia
• papillary muscle dysfunction
• infarction expansion
• rupture
• aneurysm
• thrombus

Question 12

possible outcomes of MI

by timing

Answer 12

immediate

• v fib -> cardiac death
• arrhythmia

<2wks

• fibrinous pericarditis
• mural thrombosis
• ventricular rupture

> 2wks

• progressive heart failure
• ventricular aneurysm

Question 13

features of congestive HF

Answer 13

(ABCDE)

• alveolar edema
• kerley B lines - subpleural interstitial edema
• cardiomegaly (more than half the span of the thoracic diameter)
• diversion of upper lobe - reflects elevated LA pressure
• pleural effusions

Question 14

LHF cause

Answer 14

• IHD
• HTN
• aortic/mitral valvular heart diseases
• myocardial diseases

Question 15

LHF clinical symptoms

Answer 15

forward failure: blood cannot enter aorta

- congestion in lungs - breathlessness

Question 16

causes of RHF

Answer 16

- LHF
 pulmonary diseases (cor pulmonale)

Question 17

RHF clinical symptoms

Answer 17

backward failure
congestion in liver -> hepatomegaly
edema of lower limbs