SAQ: Anti-anginals

Question 1

3 types of therapy

Answer 1

1. Nitrates
2. Beta-blockers
3. Ca channel blockers

Question 2

Nitrates

Answer 2

• Promote production of endothelium-derived relaxing factor (EDRF- including NO)
• Cause vasodilatation
• Increase coronary vessel perfusion to relieve ischaemia
• Short-acting to abort an attack
• Long-acting used prophylactically

Question 3

Beta-blockers

Answer 3

• Decrease myocardial oxygen demand by lowering work of the heart
• Used prophylactically for exercise-induced (stable) angina

Question 4

Ca Channel blockers

Answer 4

• Useful in chronic state angina
• Effective in varient angina by directly preventing coronary artery vasospasm
• In vitro, vasodilatation, negative chronotropy and inotropy
• In vivo, baroreceptor reflex opposes this and net effect is balance of direct and reflex actions