(11.1) Drugs Used in Chronic Ischemic Heart Disease (Konorev) Flashcards
How is chronic ischemic heart disease characterized?
PARTIAL occlusion of coronary artery
What are some examples of chronic ischemic heart disease?
- Angina
- Variant (Prinzmental) angina
Angina:
What causes?
When do symptoms occur?
Occlusion of coronary arteries resulting from the formation of atherosclerotic plaque
Symptoms occur during exertion/stress
Variant (Prinzmental) angina:
What causes?
When do symptoms occur?
Episodes of vasoconstriction of coronary arteries
Symptoms occur at rest
What are the two general approaches to treat angina?
- Decrease cardiac work
- Increase blood flow through coronary arteries
What is a direct approach to treat angina?
Surgical:
To increase (or restore) coronary blood flow
-Atherectomy : Tip of catheter shears off the plaque
- Coronary artery bypass grafting
- Percutaneous transluminal coronary angioplasty (PTCA)
-Stent : Expandable tube used as scaffolding to keep vessel open
What pharmacologic agents can be used to treat vasospastic (Prinzmetal) angina?
Vasodilators
Can you use vasodilators to treat angina pectoris?
NO!
Vasodilators are NOT useful in atherosclerotic angina
Due to “coronary steal” phenomenon : Administering a arteriolar vasodilator will FURTHER exacurbate the ischemic area by further dilating the perfused myocardium and increasing blood flow to healthy tissue
What is the best way to treat angina pectoris?
DECREASE myocardial oxygen demand
C. Pilocarpine
What are the three classes of drugs used in chronic IHD?
Nitrates (nitrovasodilators)
Calcium channel blockers
Beta-blockers
What are the 3 nitrovasodilator drugs?
Nitroglycerin
Isosorbide dinitrate
Isosorbide mononitrate
Describe the MOA of nitrates
What is a major drawback of using nitrates?
Development of tolerance
Describe the mechanism of nitrate tolerance
Depletion of thiol compounds
Increased generation of superoxide radicals
Reflex activation of sypmathetic nervous system (tachycardia, decreased coronary supply)
Retention of salt and water
E. Activation of protein kinase G
What are the two categories of calcium channel blockers used in the treatment of angina?
Non-cardioactive
Cardioactive
What are the non-cardioactive CCBs?
Amlodipine
Nifedipine
Nicardipine
Which of the non-cardioactive CCBs are long acting vs short acting?
Amlodipine = long acting, t1/2=30-50h
Nifedipine = short acting, t1/2=4h
Nicardipine = short acting, t1/2=2-4h
What are the cardioactive CCBs?
Diltiazem
Verapamil
Describe the MOA of calcium channel blockers
Ca2+ channel blockers inhibit Ca2+ from entering the cell to cause contraction
What beta-blockers are indicated in angina?
Propranolol
Nadolol
Metoprolol
Atenolol
What is the MOA of beta blockers in the treatment of angina?
Decreased myocardial oxygen demand
D. Decreased coronary vascular tone
A. Diltiazem
