Drugs Used in Stable and Vasospastic Angina Flashcards
What are the two ways to approach treating angina pectoris?
- Reduce oxygen demand
- Increase oxygen supply
What are ways to increase coronary blood flow?
- Coronary artery bypass grafting
- Percutaneous coronary intervention
- Stent
Can pharmacotherapy be used to increase blood flow through a stenotic coronary artery?
NO
What are the drugs in the nitrate drug class?
- Nitroglycerin
- Isosorbide dinitrate
- Isosorbide mononitrate
What is the relationship between nitrates and first pass metabolism?
- Nitrates have significant first pass metabolism due to high nitrate reductase activity in liver
How does the liver affect the bioavailability of nitrates? How can this be fixed?
- When taken orally, bioavailability is low but can be fixed by using other routes of administration
Which specific nitrate drug is a poor substrate of nitrate reductase? What is the result of this?
- Isosorbide mononitrate
- Results in increased bioavailability
What is the MOA of nitrates?
- Nitrates form NO which cause venous dilation allowing for a reduced preload. The reduced preload causes a decrease in O2 demand, helping the stable angina
What are some ways someone could become tolerant of nitrate compounds?
- Depletion of thiol compounds
- Increased superoxide radicals
- Reflex activation of sympathetic nervous system
- Retention of salt and water
Which specific drugs are used as short acting drugs? Why?
- Nitroglycerin and isosorbide dinitrate (spray or SL)
- Used to relieve angina attack
Which specific drugs are used as long acting drugs? Why?
- Nitroglycerin, Isosorbide dinitrate, and Isosorbide mononitrate (oral)
- Used to prevent angina attacks
What are some adverse effects of nitrates?
- Headaches due to meningeal vasodilation (don’t use in intracranial pressure)
- Orthostatic hypotension
- Increased sympathetic discharge
- Increased renal Na+ and H2O reabsorption
What are some drug interactions with nitrates?
- Interacts with drugs used in ED
What are some non-cardioactive calcium channel blockers used to treat stable angina?
- Amlodipine
- Nifedipine
- Nicardipine
Which non-cardioactive CCBs is a long acting drug?
- Amlodipine
Which non-cardioactive CCBs are short acting?
- Nifedipine
- Nicardipine
What are some cardioactive CCBs used in treating stable angina?
- Diltiazem
- Verapamil
What is the MOA of CCBs?
- CCBs block calcium influx in different cell types
What cell types does non-cardioactive CCBs affect?
- Vascular smooth muscle
What cell types does cardioactive CCBs affect?
- Vascular smooth muscle
- Cardiac muscle
- Cardiac pacemaker cells
What is the main goal of CCBs in treating stable angina?
- Decrease myocardial O2 demand
- How do CCBs reduce the myocardial O2 demand?
- Dilation of peripheral arterioles
- Decreased cardiac contractility (cardioactive)
- Reduced heart rate (cardioactive)
What are some major adverse effects of CCBs?
- Cardiac depression, cardiac arrest, and acute heart failure
- Bradycardia, AV block
- Severe hypotension
- Vasodilation triggers reflex sympathetic activation (nicardipine, nifedipine)
- Nifedipine increases risk of MI in patients with HTN
What are some minor adverse effects of CCBs?
- Flushing, headache, anorexia, dizziness
- Peripheral edema
- Constipation (verapamil)
