Drugs Stable Angina

Question 1

What does the myocardium require to meet oxygen demand?

Answer 1

Collateral blood supply

Question 2

What can arterial stiffness lead to?

Answer 2

Ventricle hypertrophy

Question 3

Define atherosclerosis

Answer 3

Growth of LDL-cholesterol plaques in sub-endothelium

Question 4

What does myocardial ischaemia lead to?

Answer 4

Large lactate quantities generated from pyruvate due to myocardial anaerobic glycolysis = exertional chest pain
Ischaemic tissue beyond narrowing coronary artery struggles to produce ATP from krebs so switches to glycolysis

Question 5

What are the symptoms of stable angina?

Answer 5

• Crushing, burning, tight chest pain, SOB, nausea, sweating

- Worse by physical exertion but relieved few mins rest

Question 6

What are the symptoms of acute coronary syndrome (ACC)?

Answer 6

• Symptoms appear at rest
• Occasionally due to vasospasm
• Usually indicate plaque rupture with thrombus narrowing coronary artery

Question 7

What sign on an ECG indicates myocardial ischaemia?

Answer 7

ST depression / elevation shows MI

Question 8

What can coronary angiography be used to identify?

Answer 8

Narrowing + occlusion of coronary arteries

Question 9

What can an echo be used to identify?

Answer 9

Chamber wall motion abnormalities > may indicate CAD

Question 10

Give an example of symptomatic relief for IHD

Answer 10

Drugs that reduce/relieve angina symptoms associated with exertion ischaemic stress
e.g. GTN

Question 11

Give an example of preventative relief for IHD

Answer 11

Drugs used prophylactically to reduce incidence of angina episodes
e.g. Bisoprolol

Question 12

What is the MOA of organic nitrates?

Answer 12

e. g. GTN
- Nitrates = modified to produce NO
- NO activates guanylyl cyclase
- cGMP produced activates PKG
- PKG prevents Ca entry

Body desensitises to it over time

Question 13

What is one of the best pharmacological means of reducing CAD risk?

Answer 13

Lowering serum LDL if over 5.2mm/L with statins

Works for familial + diet related hypercholesterolaemia

Question 14

What is the MOA of B-blockers?

Answer 14

e. g. Bisoprolol
- Competitively inhibit B1 adrenoreceptors in cardiac tissue
- Prevents binding of agonist (noradrenaline + adrenaline)
- -ve chronotrope + intotrope = reduced CO
- Prevent HR increasing

Question 15

What is the side effect of B-blockers

Answer 15

Running through treacle

Question 16

What is the MOA of Ca channel blockers?

Answer 16

e. g. Dialtizem
- Stops Ca traffic through L-type VGC in nodes + myocytes
- -ve chronotrope + inotrope
- Crosses membrane & causes conformational change of channel so it remains inactive
- Relaxes VSMC’s = vasodilation

Question 17

What is Nicorandil and what is its MOA?

Answer 17

• Alternative treatment stable angina
• Coronary vasodilator
• Stimulates guanylyl cyclase to increase cGMP = reduces Ca entry into VSMC
• Activates K/ATP channel effluxer, hyperpolasiring cell = prevents VG Ca channel activity

Question 18

What is Ivabradine and what is its MOA?

Answer 18

• Alternative treatment stable angina
• Rate limiter
• Inhibits Na/K inward current in SAN
  = reduced pacemaker automaticity/impulse frequency