Angina Pectoris Flashcards
Classic Angina vs Variant Angina
CA: occlusion of the coronary arteries resulting from the formation of atherosclerotic plques
VA: spontaneous vasoconstriction of coronary arteries
When do symptoms occur for CA?
Exertion/stress
Risk Factor for CA?
High Cholesterol
Origin of VA?
Genetic
When do symptoms occur for VA?
At Rest
General Drug mechanisms used to treat stable angina pectoris (2)
- Drugs that reduce o2 demand
2. Drugs that increase o2 supply
How can drugs reduce o2 demand?
Decrease cardiac work by:
- Decrease HR
- Decrease force of contraction
- Decrease Preload
What is used to treat stable angina pectoris (5)
- Organic Nitrates
- Beta Blockers
- CCBs
- Combo therapy
- Surgery
Beneficial effects of vasodilators in the treatment of angina (2)
- Dilation of veins
- Dilation of the coronary arteries
* dilating arterioles is NOT beneficial for tx of angina
What are CCBs particularily useful for? What are they not effective against?
- Variant Angina
2. Classic Angina
How do organic nitrates effect o2 supply and demand?
- Dilate veins = Decrease preload and o2 demand
2. Dilate large arteries = increase o2 supply
What type of angina are organic nitrates used for?
Both Classic and Variant
Most important nitrate drugs are (3)?
- Nitroglycerine
- Isosorbide Di-nitrate
- Isosorbide Mono-Nitrate
How is nitroglycerine administered and why?
Sublingually or transdermally because it is inactivate by 1st pass metabolism
What limits the utility of nitrate drugs for tx?
Tolerance
What are the compensatory responses to nitrate drugs?
Reflex tachycarida
*May require co-therapy w/ Beta blocker
Toxic effects of Nitrate Drugs?
Headache: 30%
Flushing/sweating
Hypotension
Mechanism of action of nitrate drugs
- Denitration
- Cross membrane to vascular smooth muscle cell
- Combines w/ guanylyl cyclase to convert GTP to cGMP
- cGMP opens K channel causing hyperpolarization and smooth muscle relaxation
How do beta blockers help treat angina?
Block Beta-Adrenergic receptors causing:
- Decreased HR
- Decreased contractile Force
- -> Decrease O2 Demand
what type of angina are Beta blockers used for?
Classic Only
-may precipitate vasospasms in people w/ variant angina
What should beta blockers be given with? why?
Organic nitrates
Blocks increases in o2 demand resulting from reflex tachycardia
What should you avoid doing w/ beta block therapy that could precipitate a heart attack?
Avoid rapid termination
How do CCBs work in general?
Block L-Type Voltage Dependent Calcium channels on cardiac and/or Vascular smooth muscle
What are the non-cardioactive CCBs
- Amlodipine
- Nifedipine
