Antianginal Drugs Flashcards
Angina Pectoris (Chest Pain)
When the supply of oxygen and nutrients in the blood is insufficient to meet the demands of the heart, the heart muscle “aches.”
The heart requires a large supply of oxygen to meet the demands placed on it.
Ischemia
Poor blood supply to an organ
Ischemic heart disease
Poor blood supply to the heart muscle
Atherosclerosis
Coronary artery disease
Myocardial infarction
Necrosis, or death, of cardiac tissue
Disabling or fatal
Five different kinds of angina have been identified, with the two most common being
stable angina (also called classic or effort angina)
unstable angina (also called pre-infarction angina)
Other types include:
Variant (also called vasospastic or Prinzmetal angina)
Atypical
Microvascular
Symptoms of Angina
The symptoms of angina are different for different people, but regardless, they are usually experienced after heavy exercise or because of emotional stress.
Learn to recognize and pay attention to the following symptoms:
-pain that begins in the middle of your chest and then spreads to your left arm, back, neck or jaw; usually this is not a sharp pain, but a dull one
-a feeling of pressure, tightness or squeezing in your chest or arms
-a feeling of persistent indigestion that is moderate or severe
-numbness, or a lack of feeling in your arms, shoulders or wrists
Stable Angina
Stable angina occurs when the heart has to work harder than normal, during exercise, for example.
It has a regular pattern, and if you already know that you have stable angina, you will be able to predict the pattern.
Once you stop exercising, or take medication (usually nitroglycerin) the pain goes away, usually within a few minutes.
Stable Angina Characteristics
The symptoms vary according to the type of angina you have. If, for example, you have stable angina, the pain or discomfort:
-happens when your heart has to work harder, during exercise for example
-is no surprise to you, and feels the same each time it happens
-usually lasts less than 5 minutes, and stops if you rest or take medication
-might feel like indigestion
Unstable Angina
Unstable angina is more serious, and may be a sign that a heart attack could happen soon.
There is no predictable pattern to this kind of angina; it can just as easily occur during exercise as it can while you are resting. It should always be treated as an emergency.
People with unstable angina are at increased risk for heart attacks, cardiac arrest, or severe cardiac arrhythmias (irregular heartbeat or abnormal heart rhythm).
Unstable Angina Characteristics
Unstable angina is different.
The pain or discomfort:
-often happens when you are sleeping or resting takes you by surprise
-might last as long as 30 minutes and might become progressively worse
-cannot be relieved with rest or medication
-might be a sign of a heart attack that will happen soon
*Unstable angina tends to happen more often in older adults.
Women and Angina
For example, a woman may have chest pain that feels like a stabbing, pulsating or sharp form of chest pain rather than the more typical vise-like pressure.
Women are also more likely to experience symptoms, such as nausea, shortness of breath or abdominal pain.
These differences may lead to delays in seeking treatment.
Purpose of Drug Therapy for Angina
increase 02 supply, decrease 02 demand
3 Drugs for Angina
Nitrates and nitrites
ß-Blockers
Calcium channel blockers
Therapeutic Objectives of antianginal drugs
To minimize the frequency of attacks and decrease the duration and intensity of anginal pain
To improve the patient’s functional capacity with as few adverse effects as possible
To prevent or delay myocardial infarction, the worst possible outcome.
Overall goal: INCFEASE blood flow to ischemic mycardium, DECREASE myocardial O2 demand or both
Forms of Nitrates and Nitrites
Sublingual*
Chewable tablets
Oral capsules/tablets
Intravenous solutions*
Transdermal patches*
Ointments
Translingual sprays*
*Bypass the liver and the first-pass effect.
Nitrates Mechanism of Action andDrug Effects
Cause vasodilation because of relaxation of smooth muscles
Potent dilating effect on coronary arteries
Result: oxygen to ischemic myocardial tissue
Used for prevention and treatment of angina
Rapid- and Long-Acting Nitrates and Nitrites
Rapid-acting forms
-Used to treat acute anginal attacks
-Sublingual tablets or spray; IV infusion
Long-acting forms
-Used to prevent anginal episodes
Nitroglycerin
(both rapid and long acting)
Prototypical nitrate
The most important drug used in the symptomatic treatment of ischemic heart conditions such as angina
Routes: oral, sublingual, metered-dose aerosol that is sprayed under the tongue, intravenous, and topical
