Chapter 23 Antianginal drugs

Question 1

Under ischemic conditions when the myocardium is deprived of oxygen, the heart shifts to anaerobic metabolism to meet its energy needs. One of the by-products of anaerobic metabolism is lactic acid. Accumulation of lactic acid and other metabolic by-products causes?

Answer 1

pain receptors surrounding the heart to be stimulated, which produces the heart pain know as angina.

Question 2

Angina pectoris (chest pain) occurs because of a?

Answer 2

mismatch between the oxygen supply and oxygen demand, with either too high a demand for oxygen or too little oxygen delivery.

Question 3

Coronary artery disease is an abnormal condition of the arteries that delivers oxygen to the heart muscle. These arteries may become narrowed, which results in reduced flow of oxygen and nutrients to the myocardium. Poor blood supply to an organ is referred to as ischemia. The condition is called ischemic heart disease. What happens when the coronary arteries that deliver oxygen to the heart muscle become blocked?

Answer 3

a heart attack or myocardial infarction (MI) occurs.

Question 4

Many substances and situations can increase heart rate and contractility and oxygen demand, including caffeine, exercise, and stress, and result in stimulation of the?

Answer 4

sympathetic nervous system (SNS), leading to increased heart rate and contractility.

Question 5

Some of the drugs used to treat angina are aimed at?

Answer 5

correcting the imbalance between myocardial oxygen supply and demand by decreasing heart rate and contractility.

Question 6

There are three classic types of chest pain, or angina pectoris.

Answer 6

Chronic stable angina
Unstable (preinfarction) angina
Vasospastic angina

-Dysrhythmias and electrocardiogram (ECG) changes often accompany these different types of anginal attacks.

Question 7

Chronic stable angina has?

Answer 7

atherosclerosis as its primary cause. Chronic stable angina can be triggered by exertion or other stress, as well as nicotine in tobacco, alcohol, coffee, and other drugs that stimulate the SNS. The pain of chronic stable angina is commonly intense but subsides within 15 minutes of either rest or appropriate antianginal drug therapy.

Question 8

Unstable (preinfarction) angina is usually the?

Answer 8

early stage of progressive coronary artery disease, often ending in an MI in subsequent years. Another term for this type of angina is crescendo angina, because the pain increases in severity, as does the frequency of attacks. Later, pain may even occur while the patient is at rest.

Question 9

Vasospastic angina results from?

Answer 9

spasms in the layer of smooth muscle that surrounds atherosclerotic coronary arteries, often occurring at rest and without any precipitating cause, but following a regular pattern, such as the same time of day. This type of angina is also called Prinzmetal angina or variant angina.

Question 10

The three main classes of drugs used to treat angina pectoris are:

Answer 10

(1) nitrates and nitrites
(2) beta blockers
(3) calcium channel blockers (CCBs)

Question 11

There are three main therapeutic objectives of antianginal drug therapy:

Answer 11

(1) minimizing the frequency of attacks and decrease the duration and intensity of the anginal pain
(2) improving the patient’s functional capacity with as few adverse effects as possible
(3) preventing or delaying the worst possible outcome, MI

Question 12

The overall goal of antianginal drug therapy is?

Answer 12

to increase blood flow to ischemic myocardium, decrease myocardial oxygen demand, or both.

Question 13

Nitrates have long been the mainstay for both the?

Answer 13

prophylaxis and treatment for angina.

Question 14

The rapid- and long-acting nitrates available for clinical use include amyl nitrite (rapid acting), nitroglycerin (both
rapid and long-acting), isosorbide dinitrate (both rapid
and long-acting), and isosorbide mononitrate (primarily long-acting).

Answer 14

.

Question 15

Antianginal Calcium Channel Blockers (CCBs)
Diltiazem (Cardizem):
Verapamil (Calan):

Answer 15

• Diltiazem (Cardizem): It is the only benzothiazepine CCB; effective for tx of angina pectoris. Available in parenteral form used in atrial fibrillation; Cardizem SR taken twice/day; Cardizem CD taken once/day.
• Verapamil (Calan): Has similar indications as Cardizem

Question 16

Calcium Channel Blockers CCBs Mechanism of Action:

Answer 16

Inhibits transport of Ca+ into myocardial and vascular smooth muscle cells= inhibition of excitation of muscles and promotes muscle relaxation of smooth muscles surrounding the coronary arteries; this dilates and increases blood flow and lowers SVR (systemic vascular resistance; force against the heart).

Question 17

CCB Indications:

Answer 17

Angina, HTN, Prinzmetal’s angina, arrhythmias, short-term treatment of Reynaud’s disease.

Question 18

CCB Contraindications:

Answer 18

Acute MI, 2nd or 3rd degree AV block (unless pt. has pacemaker), hypotension

Question 19

Adverse Effects for CCBs

Answer 19

Hypotension, arrhythmias, palpitations, syncope, peripheral edema, bradycardia, Rash, dyspnea, and Stevens-Johnson syndrome.

Question 20

CCBs Drug Interactions:

Answer 20

Grapefruit juice= decreased metabolism of CCBs

Beta Blockers= additive effects

Question 21

Beta blockers are also used to relieve angina and do so by?

Answer 21

decreasing the heart rate, reducing workload on the heart, and decreasing oxygen demands.

Question 22

Exercise-induced spasms in atherosclerotic coronary arteries can also be reversed or prevented by?

Answer 22

administration of nitrates, encouraging healthy physical activity in patients.

Question 23

The nitrates are used to treat?

Answer 23

stable, unstable, and vasospastic (Prinzmetal) angina.

Question 24

If the goal of treatment is to abort or treat a sudden attack of angina, then rapid onset of action is needed, such as with?

Answer 24

IV infusion, sublingual tablet, and/or translingual spray, with pharmacokinetics that allow quick entry of the drug into the bloodstream.

Question 25

Long-acting dosage forms of nitrates are used more for?

Answer 25

prevention of anginal episodes.

Question 26

Nitrates are well tolerated, and most adverse effects are usually transient and involve the cardiovascular system. The most common undesirable effect is?

Answer 26

headache, which generally diminishes soon after the start of therapy. Other cardiovascular effects include tachycardia and postural hypotension.

Question 27

If nitrate-induced vasodilation occurs too rapidly, the cardiovascular system overcompensates and?

Answer 27

increases the heart rate, a condition referred to as reflex tachycardia.

• may occur w/significant vasodilation that involves the systemic veins
• there is a large shift in blood volume toward the systemic venous circulation and away from the heart
• baroreceptors (BP receptors) in the heart then falsely sense that there has been a loss of blood volume
• at this point, the heart begins beating more rapidly to move the apparently smaller volume of blood more quickly throughout the body, especially toward vital organs (including the heart itself). However the same baroceptors soon sense there has been a loss of blood volume but that the volume of blood missing in the heart is now in the periphery (venous system) and the HR slows back to normal

Question 28

Topical nitrate dosage forms can produce various types of?

Answer 28

contact dermatitis (skin inflammation), but these are actually reactions to the dosage delivery system & not nitroglycerin itself; thus not a true drug allergic reaction 
-document type of reaction so clinicians do not avoid this drug class if reaction is only contact dermatitis

Question 29

Tolerance to the antianginal effects of nitrates can occur
surprisingly quickly in some patients, especially those taking long-acting formulations or taking nitrates around the clock. Cross-tolerance arises when?

Answer 29

Cross-tolerance arises when patients receive more than one nitrate dosage form. To prevent this, nitrate-free periods allow certain enzymatic pathways to replenish themselves.
-common regimen w/transdermal patches is to remove them at night for 8 hrs & apply new patch in the morning. Shown to prevent tolerance to the beneficial effects of nitrates

Question 30

Nitrates interactions

Answer 30

Nitrate antianginal drugs can produce additive hypotensive effects when taken in combination with alcohol, beta blockers, CCBs, phenothiazines, and erectile dysfunction drugs (numerous deaths w/erectile dysfunction)

Question 31

Nitrates: Nitroglycerin

Answer 31

• abbreviated NTG or TNG
• traditionally been most important drug used in the symptomatic Tx of ischemic heart conditions such as angina
• when given orally, it goes to the liver to be metabolized before it becomes activated in the body. During this process a large amount of nitroglycerin is removed from the circulation (large first-pass effect). Due to this it is administered by other routes
• Tablets by sublingual routes Tx for acute onset & prevention of angina
• sublingual tablets must be stored in original container because exposure to air & moisture can inactivate the drug
• IV form used for BP control in HTN pt’s; tx of ischemic pain, heart failure, & pulmonary edema associated w/acute MI; & hypertensive emergencies
• oral & topical formulations=long term prophylatic management of angina pectoris
• patches worn for 12-14 hrs

Question 32

The beta 1 receptors are located in the hearts conduction system & throughout the myocardium. Beta receptors normally stimulated by the binding of the neurotransmitters epinephrine and norepinephrine

Answer 32

.

Question 33

When beta receptors are blocked by beta blockers what happens?

Answer 33

the rate at which the pacemaker (sinoatrial node) fires decreases, and the time it takes for the node to recover increases. The beta blockers also slow conduction through the atrioventricular node and reduce myocardial contractility. Both effects serve to slow the heart rate and reduce myocardial oxygen demand, which aids in the treatment of angina by reducing the workloadnof the heart.
- slowing the HR is beneficial in pt’s w/ischemic heart disease because the coronary arteries have more diastolic time to fill with oxygen nutrient rich blood & deliver these substances to myocardial tissue

Question 34

Following an MI, there is a high level of circulating catecholamines that will produce harmful consequences if their actions go unopposed. They cause the heart rate to increase, which leads to a further imbalance in the supply/demand ratio, and irritate the conduction system of the heart, which can result in potentially fatal dysrhythmias. The beta blockers block do what?

Answer 34

The beta blockers block all of these harmful effects, and their use has been shown to improve the chances for survival in patients after MI.

Question 35

The beta blockers also suppress the activity of the hormone renin, which is the first step in the renin-aldosterone angiotensin system. Renin is a potent vasoconstrictor released by the kidneys when they sense that they are not being adequately perfused. What happens when beta blockers inhibit the release of renin

Answer 35

Blood vessels to and in the kidney dilate, causing reduced BP

Question 36

Beta blockers indications

Answer 36

most effective in the treatment of exertional angina because the usual physiologic effects of an increase in the heart rate and systolic blood pressure that
occurs during exercise or stress is blunted by beta blockers, thereby decreasing myocardial oxygen demand.
-For an elderly patient with significant angina, “exercise” may simply be carrying out the activities of daily living (ADLs), such as bathing, dressing, or cooking.
-also for MI, HTN, cardiac dysrythmias, & essential tremor, migraine, tachycardia associated w/stage fright (low doses)

Question 37

Beta blockers contraindications

Answer 37

• systolic heart failure & serious conduction disturbances
• used w/caution in pt’s w/bronchial asthma, because any level of blockade of beta 2 receptors can promote bronchoconstriction
• diabetes mellitus (due to masking of hypoglycemia-induced tachycardia) & peripheral vascular disease

Question 38

The adverse effects of the beta blockers result from their ability to block beta-adrenergic receptors in various areas of the body, resulting in a?

Answer 38

Blocking of beta 1 receptors may lead to a decrease in heart rate, cardiac output, and cardiac contractility

• blocking of beta 2 receptors results in bronchoconstriction, and increased airway resistance in pt’s w/asthma or COPD
• may lead to cardiac rhythm problems, decreased SA and AV nodal conduction, decrease in systolic/diastolic BP, decrease renin release from kidneys
• can mask tachycardia associated w/hypoglycemia, & diabetic pt’s may not be able to tell when blood sugar falls too low
• can cause hypoglycemia and hyperglycemia
• fatigue, insomnia, weakness may occur because of negative effects on the cardiac and CNS

Question 39

Beta blockers interactions

Answer 39

1) Diuretics and antihypertensives>additive effects resulting in hypotension
2) CCBs>additive atrioventricular node suppression resulting in hypotension, bradycardia, & heart block
3) Insulin & oral antidiabetic drugs>masking of hypoglycemia effects resulting in unrecognized hypoglycemia

Question 40

Beta Blocker Drug: Atenolol

Answer 40

Cardioselective beta 1 adrenergic receptor blocker indicated for propylactic Tx of angina pectoris
-use after MI decreases mortality

Question 41

Beta blocker Drug: Metoprolol

Answer 41

Cardioselective beta 1 adrenergic receptor blocker used for prophylactic Tx of angina

• reduces mortality after MI & treating angina
• oral (immediate release & long acting), & parenteral (injectable)
• IV commonly administered to hospitalized pt’s after MI & used for Tx of HTN

Question 42

Nitrates and nitrites:

Drug: Nitroglycerin Mechanism of action

Answer 42

Nitrates dilate constricted coronary arteries, helping to increase the supply of oxygen and nutrients to the heart muscle, but they also dilate all blood vessels, predominantly affecting venous vascular beds.

• Also have a dose dependent arterial vasodilator effect.
• these vasodilatory effects are the result of relaxation of smooth muscle cells part of the wall structure of veins and arteries.
• nitrates have a potent dilating effect on the large and small coronary arteries. This causes redistribution of blood & oxygen to previously ischemic myocardial tissue & reduction of anginal symptoms
• The venous dilation results in a decrease in blood return to the heart (decreased preload), whereas the arterial dilation results in a decrease

Question 43

Nitrates and nitrites:

example Drug: Nitroglycerin indications

Answer 43

Used to treat stable, unstable, and vasospastic (Prinzmetal) angina

• long acting dosage forms used for prevention of anginal episodes
• rapid acting forms most often sublingual tablets, or an IV use for treatment of acute anginal attacks

Question 44

Nitrates and nitrites:

Example Drug: Nitroglycerin contraindications

Answer 44

• known drug allergy
• severe anemia
• closed-angle glaucoma
• hypotension
• severe head injury
• erectile dysfunction drugs

Question 45

Nursing process: Before antianginal drugs are administered, obtain a thorough past and present medical health history and medication history, and document the findings. Also measure?

Answer 45

weight, height, and vital signs, with attention to supine,
sitting, and standing blood pressures.
-report a BP reading of less than 90 mm Hg to prescriber before administering
-with any drugs affecting BP or pulse rate take the apical pulse rate for 1 full minute. If pulse rate is 60 beats/min or less or 100 beats/min or more (reflex tachycardia is an AE) contact prescriber

Question 46

If the patient is experiencing pain, what should the nurse include in the documentation?

Answer 46

description of onset, character, intensity, location, duration, precipitating factors, alleviating factors, and presence of nausea or vomiting.

Question 47

Significant interactions with antianginal drugs include?

Answer 47

alcohol, beta blockers, CCBs, phenothiazines, and erectile dysfunction drugs, such as sildenafil, tadalafil, and vardenafil.
-Taking these drugs with nitrates will result in worsening of hypotensive responses, paradoxical bradycardia, and a resultant increase in angina with subsequent significant risk of cardiac or cerebrovascular complications due to the decreased perfusion.

Question 48

Elderly patients often have difficulty with blood pressure control because of the occurrence of normal age-related periods of hypotension, and the use of antianginals may?

Answer 48

lead to worsening of hypotensive responses.

Question 49

If patients are taking long term nitrates on a daily basis, what is it important to assess?

Answer 49

Continued therapeutic responses because of the development of tolerance to the drugs effects.

Question 50

Concerns arise with the use of nonselective beta blockers and beta2 blockers in patients with bronchospastic disease because of the?

Answer 50

drug-related effects of bronchoconstriction and increased airway resistance, which results in wheezing and dyspnea as adverse effects.
-therefor if asthma or other respiratory problems are present, beta blockers would NOT be indicated because bronchoconstriction could be exacerbated

Question 51

There is concern about use of beta blockers in patients w/peripheral vascular disease, hypotension, hyperglycemia or hypoglycemia and bradycardia. Nonselective beta blockers may also exacerbate?

Answer 51

Preexisting heart failure. Assessment for edema is important in pt’s with cardiac risk factors. If weight gain is of 2 lbs or more in 24 hours or 5lbs or more in a week should be reported to prescriber

Question 52

In patients taking CCBs, assess for possible drug-food interactions and toxicity, including?

Answer 52

grapefruit juice, which reduces the metabolism of nifedipine leading to possible toxicity; grapefruit must be AVOIDED

Question 53

Nursing assessment for CCB Diltiazem (Cardizem)

Answer 53

• available in several sustained delivery forms; closely assess order to avoid medication error
• cautious use is important in pt’s w/history of hypotension, palpitations, tachy/brady cardia, constipation, dyspnea & edema

Question 54

Nursing implementation for Antianginal drugs

Answer 54

Always review and/or record the patient’s vital signs and description of chest pain for the duration of therapy.

Question 55

Nursing implementation for antianginal drugs:

For any dosage form what should the nurse do?

Answer 55

-Administer while pt is seated to avoid falls/injury from drug induced hypotension (may last for 30 min)

Question 56

Nursing implementation for antianginal drugs: When administering nitrates what should the nurse monitor?

Answer 56

The patients chest pain on a scale of 0-10 before, during, and after therapy.

Question 57

For antianginal drugs the nurse should monitor the pt’s response to drug therapy by?

Answer 57

Measuring the pt’s BP & pulse rate & assessing for the presence of HA, dizziness, &/or lightheadedness.

Question 58

When pt is in supine position, an appropriate dose of nitrate will produce a clinical response of a decrease in BP of about?
When should the prescriber be notified?

Answer 58

10 mm Hg and/or an increase in HR of 10 beats/min.
- notify prescriber if systolic BP of 90 mm Hg or less and/or a pulse rate of 60 beats/min or less or a pulse rate of 100 beats/min or more

Question 59

Nursing implementation: for oral dosage forms what should the nurse do?

Answer 59

1) taken as ordered before meals and 6 oz of water
2) extended release preparations don’t crush, chewed or altered. Acetaminophen may be given if there is a drug-related HA

Question 60

Antiangina Nursing implementation: for sublingual forms

Answer 60

1) place under tongue, do NOT swallow until drug has dissolved
2) metered dose aerosol sprays are applied onto or under tongue
3) keep nitrates in original packaging/container. Exposure to light, plastic, cotton filler, and moisture but be avoided

Question 61

Antiangina Nursing implementation: for ointment

Answer 61

1) use proper dosing paper supplied to apply a thin layer to clean, dry, hairless skin of upper arms/body. Avoid below knees/elbows
2) Do NOT apply w/fingers unless wearing gloves
3) Do NOT rub ointment in, cover area w/occlusive dressing if not provided
4) rotate sites & remove all residual w/soap & water & pat dry

Question 62

Antiangina Nursing implementation: for transdermal forms

Answer 62

1) apply to clean, residue-free, hairless area, & rotate sites
2) if cardioversion or use of an automated electrical defibrillator is required, remove patch to avoid burning of the skin & damage to defibrillator paddles
3) before new patch applied, locate/remove old patch & clean skin. Carefully dispose of used, unneeded, or defective patches. Flush down de el toilete