Study Guide Chapter 33 Coronary Artery Disease and Acute Coronary Syndrome Flashcards Preview

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Which patient is most likely to be in the fibrous stage of development of coronary artery disease (CAD)?

a. Age 40, thrombus adhered to the coronary artery wall
b. Age 50, rapid onset of disease with hypercholesterolemia
c. Age 32, thickened coronary arterial walls with narrowed vessel lumen
d. Age 19, elevated low-density lipoprotein (LDL) cholesterol, lipid-filled smooth muscle cells

c. Age 32, thickened coronary arterial walls with narrowed vessel lumen

Rational: The fibrous plaque stage has progressive changes that can be seen by age 30. Collagen covers the fatty streak and forms a fibrous plaque in the artery. The thrombus adheres to the arterial wall in the complicated lesion stage. Rapid onset of coronary artery disease (CAD) with hypercholesterolemia may be related to familial hypercholesterolemia, not a stage of CAD development. The fatty streak stage is the earliest stage of atherosclerosis and can be seen by age 20.


What accurately describes the pathophysiology of CAD?

a. Partial or total occlusion of the coronary artery occurs during the stage of raised fibrous plaque
b. Endothelial alteration may be caused by chemical irritants such as hyperlipidemia or by tobacco use
c. Collateral circulation in the coronary circulation is more likely to be present in the young patient with CAD
d. The leading theory of atherogenesis proposes that infection and fatty dietary intake are the basic underlying causes of atherosclerosis

b. Endothelial alteration may be caused by chemical irritants such as hyperlipidemia or by tobacco use

Rational: The etiology of CAD includes atherosclerosis as the major cause. The pathophysiology of atherosclerosis development and resulting atheromas is related to endothelial injury and inflammation, which can be the result of tobacco use, hyperlipidemia, hypertension, toxins, diabetes mellitus, hyperhomocysteinemia, and infection causing a local inflammatory response in the inner lining of the vessel walls. Partial or total occlusion occurs in the complicated lesion stage. Extra collateral circulation occurs in the presence of chronic ischemia. Therefore it is more likely to occur in an older patient


While obtaining patient histories, which patient does the nurse identify as having the highest risk for CAD?

a. A white man, age 54, who is a smoker and has a stressful lifestyle

b. A white woman, age 75, with a BP of 172/100 mm Hg and who is physically inactive

c. An Asian woman, age 45, with a cholesterol level of 240 mg/dL and a BP of 130/74 mm Hg

d. An obese Hispanic man, age 65, with a cholesterol level of 195 mg/dL and a BP of 128/76 mm Hg

b. A white woman, age 75, with a BP of 172/100 mm Hg and who is physically inactive

Rational: This white woman has one unmodifiable risk factor (age) and two major modifiable risk factors (hypertension and physical inactivity). Her gender risk is as high as a man's because she is over 65 years of age. The white man has one unmodifiable risk factor (gender), one major modifiable risk factor (smoking), and one minor modifiable risk factor (stressful lifestyle). The Asian woman has only one major modifiable risk factor (hyperlipidemia) and Asians in the United States have fewer myocardial infarctions (MIs) than do whites. The Hispanic man has an unmodifiable risk factor related to age and one major modifiable risk factor (obesity). Hispanics have slightly lower rates of CAD than non-Hispanics whites or African Americans


While teaching women about the risks and incidence of CAD, what should the nurse emphasize?

a. Smoking is not as significant a risk factor for CAD in women as it is in men.

b. Women seek treatment sooner than men when they have symptoms of CAD.

c. Estrogen replacement therapy in postmenopausal women decreases the risk for CAD.

d. CAD is the leading cause of death in women, with a higher mortality rate after MI than in men.

d. CAD is the leading cause of death in women, with a higher mortality rate after MI than in men.

Rational: CAD is the number-one killer of American women and women have a much higher mortality rate within 1 year following MI than do men. Smoking carries specific problems for women because smoking has been linked to a decrease in estrogen levels and to early menopause and it has been identified as the most powerful contributor to CAD in women under the age of 50. Fewer women than men present with classic manifestations and women delay seeking care longer than men. Recent research indicates that estrogen replacement does not reduce the risk for CAD, even though estrogen lowers low-density lipoprotein (LDL) and raises high-density lipoprotein (HDL) cholesterol.


Which characteristics are associated with LDLs (select all that apply)

a. Increases with exercise

b. Contains the most cholesterol

c. Has an affinity for arterial walls

d. Carries lipids away from arteries to liver

e. High levels correlate most closely with CAD

f. The higher the level, the lower the risk for CAD

b. Contains the most cholesterol
c. Has an affinity for arterial walls
e. High levels correlate most closely with CAD

Rational: LDLs contain more cholesterol than the other lipoproteins, have an attraction for arterial walls, and correlate most closely with increased incidence of atherosclerosis and CAD. HDLs increase with exercise and carry lipids away from arteries to the liver for metabolism. A high HDL level is associated with a lower risk of CAD.


Which serum lipid elevation, along with elevated LDL, is strongly associated with CAD?

a. Apolipoproteins

b. Fasting triglycerides

c. Total serum cholesterol

d. High-density lipoprotein (HDL)

b. Fasting triglycerides

Rational: Elevated fasting triglyceride levels are associated with cardiovascular disease and diabetes. Apolipoproteins are found in varying amounts on the HDLs and activate enzyme or receptor sites that promote removal of fat from plasma, which is protective. The apolipoprotein A and apolipropotein B ratio must be done to predict CAD. Elevated HDLs are associated with a lower risk of CAD. Elevated total serum cholesterol must be calculated with HDL for a ratio over time to determine an increased risk of CAD


The laboratory tests for four patients show the following results. Which patient should the nurse teach first about preventing CAD because the patient is at the greatest risk for CAD even without other risk factors?

a. Total cholesterol: 152 mg/dL, triglycerides: 148 mg/dL, LDL: 148 mg/dL, HDL: 52 mg/dL

b. Total cholesterol: 160 mg/dL, triglycerides: 102 mg/dL, LDL: 138 mg/dL, HDL: 56 mg/dL

c. Total cholesterol: 200 mg/dL, triglycerides: 150 mg/dL, LDL: 160 mg/dL, HDL: 48 mg/dL

d. Total cholesterol: 250 mg/dL, triglycerides: 164 mg/dL, LDL: 172 mg/dL, HDL: 32 mg/dL

d. Total cholesterol: 250 mg/dL, triglycerides: 164 mg/dL, LDL: 172 mg/dL, HDL: 32 mg/dL

Rational: All of this patient's results are abnormal. The patient in option c is close to being at risk, as all of that patient's results are at or near the cutoff for being acceptable. If this patient is a woman, the HDL is too low. The other patients' results are at acceptable levels.


The nurse is encouraging a sedentary patient with major risks for CAD to perform physical exercise on a regular basis. In addition to decreasing the risk factor of physical inactivity, the nurse tells the patient that exercise will also directly contribute to reducing which risk factors?

a. Hyperlipidemia and obesity

b. Diabetes mellitus and hypertension

c. Elevated serum lipids and stressful lifestyle

d. Hypertension and elevated serum homocysteine

a. Hyperlipidemia and obesity

Rational: Increased exercise without an increase in caloric intake will result in weight loss, reducing the risk associated with obesity. Exercise increases lipid metabolism and increases HDL, thus reducing CAD risk. Exercise may also indirectly reduce the risk of CAD by controlling hypertension, promoting glucose metabolism in diabetes, and reducing stress. Although research is needed to determine whether a decline in homocysteine can reduce the risk of heart disease, it appears that dietary modifications are indicated for risk reduction.


During a routine health examination, a 48-yr-old patient is found to have a total cholesterol level of 224 mg/dL (5.8 mmol/L) and an LDL level of 140 mg/dL (3.6 mmol/L). What does the nurse teach the patient based on the Therapeutic Lifestyle Changes diet (select all that apply)?

a. Use fat-free milk

b. Abstain from alcohol use

c. Reduce red meat in the diet

d. Eliminate intake of simple sugars

e. Avoid egg yolks and foods prepared with whole eggs

a, c, e.

Therapeutic Lifestyle Changes diet recommendations emphasize reduction in saturated fat and cholesterol intake. Red meats, whole milk products, and eggs as well as butter, stick margarine, lard, and solid shortening should be reduced or eliminated from diets. If triglyceride levels are high, alcohol and simple sugars should be reduced


To which patients should the nurse teach the Therapeutic Lifestyle Changes diet to reduce the risk of coronary artery disease (CAD)?

a. All patients to reduce CAD risk

b. Patients who have experienced an MI

c. Individuals with two or more risk factors for CAD

d. Individuals with a cholesterol level >200 mg/dL (5.2 mmol/L)


The Therapeutic Lifestyle Changes diet includes recommendations for all people, not just those with risk factors, to decrease the risk for CAD


A 62-year-old woman has prehypertension (BP 138/88 mm Hg) and smokes a pack of cigarettes per day. She has no symptoms of CAD but a recent LDL level was 154 mg/dL (3.98 mmol/L). Based on these findings, the nurse would expect that which treatment plan would be used first for this patient?

a. Diet and drug therapy

b. Exercise instruction only

c. Diet therapy and smoking cessation

d. Drug therapy and smoking cessation


Without the total serum cholesterol and HDL results, diet therapy and smoking cessation are indicated for a patient without CAD who has prehypertension and an LDL level ≥130 mg/dL. When the patient's LDL level is 75 to 189 mg/dL with a 10 yr risk for CVD of 7.5% or above, drug therapy would be added to diet therapy. Because tobacco use is related to increased BP and LDL level, the benefit of smoking cessation is almost immediate. Exercise is indicated to reduce risk factors throughout treatment.


What are manifestations of acute coronary syndrome (ACS) (select all that apply)?

a. Dysrhythmia

b. Stable angina

c. Unstable angina

d. ST-segment-elevation myocardial infarction (STEMI)

e. Non-ST-segment-elevation myocardial infarction (NSTEMI)

c, d, e.

Unstable angina, ST-segment-elevation myocardial infarction (STEMI), and non-ST-segment-elevation myocardial infarction (NSTEMI) are conditions that are manifestations of acute coronary syndrome (ACS). The other options are not manifestations of ACS.


Myocardial ischemia occurs as a result of increased oxygen demand and decreased oxygen supply. What factors and disorders result in increased oxygen demand (select all that apply)?

a. Hypovolemia or anemia

b. Increased cardiac workload with aortic stenosis

c. Narrowed coronary arteries from atherosclerosis

d. Angina in the patient with atherosclerotic coronary arteries

e. Left ventricular hypertrophy caused by chronic hypertension

f. Sympathetic nervous system stimulation by drugs, emotions, or exertion

b, d, e, f.

Increased oxygen demand is caused by increasing the workload of the heart, including left ventricular hypertrophy with hypertension, sympathetic nervous stimulation, and anything precipitating angina. Hypovolemia, anemia, and narrowed coronary arteries contribute to decreased oxygen supplY


What causes the pain that occurs with myocardial ischemia?

a. Death of myocardial tissue

b. Dysrhythmias caused by cellular irritability

c. Lactic acid accumulation during anaerobic metabolism

d. Elevated pressure in the ventricles and pulmonary vessels


When the coronary arteries are occluded, contractility ceases after several minutes, depriving the myocardial cells of glucose and oxygen for aerobic metabolism. Anaerobic metabolism begins and lactic acid accumulates, irritating myocardial nerve fibers that then transmit a pain message to the cardiac nerves and upper thoracic posterior roots. The other factors may occur during vessel occlusion but are not the source of pain.


What types of angina can occur in the absence of CAD (select all that apply)?

a. Silent ischemia

b. Nocturnal angina

c. Prinzmetal's angina

d. Microvascular angina

e. Chronic stable angina

c, d.

Prinzmetal's angina and microvascular angina may occur in the absence of CAD but with arterial spasm in Prinzmetal's angina or abnormalities of the coronary microcirculation. Silent ischemia is prevalent in persons with diabetes mellitus and contributes to asymptomatic myocardial ischemia. Nocturnal angina occurs only at night. Chronic stable angina refers to chest pain that occurs with the same pattern of onset, duration, and intensity intermittently over a long period of time


Which characteristics describe unstable angina (select all that apply)?

a. Usually precipitated by exertion

b. New-onset angina with minimal exertion

c. Occurs only when the person is recumbent

d. Characterized by increased duration or severity

e. Usually occurs in response to coronary artery spasm

b, d

Unstable angina is new-onset angina occurring at rest or with minimal exertion and increases in frequency, duration, or severity. Chronic stable angina is usually precipitated by exertion. Angina decubitus occurs when the person is recumbent. Prinzmetal's angina is
frequently caused by a coronary artery spasm.


Tachycardia that is a response of the sympathetic nervous system to the pain of ischemia is detrimental because it increases oxygen demand and

a. increases cardiac output.

b. causes reflex hypotension.

c. may lead to atrial dysrhythmias.

d. impairs perfusion of the coronary arteries.


An increased heart rate (HR) decreases the time the heart spends in diastole, which is the time of greatest coronary blood flow. Unlike other arteries, coronary arteries are perfused when the myocardium relaxes and blood backflows from the aorta into the sinuses of Valsalva, which have openings to the right and left coronary arteries. Thus the heart has a decreased oxygen supply at a time when there is an increased oxygen demand. Tachycardia may also lead to ventricular dysrhythmia.
The other options are incorrect


Which effects contribute to making nitrates the first-line therapy for the treatment of angina (select all that apply)?

a. Decrease preload

b. Decrease afterload

c. Dilate coronary arteries

d. Decrease HR

e. Prevent thrombosis of plaques

f. Decrease myocardial contractility

a, b, c

Nitrates decrease preload and afterload to decrease the coronary workload and dilate coronary arteries to increase coronary blood supply. The other options are not attributed to nitrates.


The patient has used sublingual nitroglycerin and various long-acting nitrates but now has an ejection fraction of 38% and is considered at a high risk for a cardiac event. Which medication would first be added for vasodilation and to reduce ventricular remodeling?

a. Captopril

b. Clopidogrel (Plavix)

c. Diltiazem (Cardizem)

d. Metoprolol (Lopressor)


Captopril (Capoten) would be added. It is an angiotensin- converting enzyme (ACE) inhibitor that vasodilates and decreases endothelial dysfunction and may prevent ventricular remodeling. Clopidogrel (Plavix) is an antiplatelet agent used as an alternative for a patient unable to use aspirin. Diltiazem (Cardizem), a calcium channel blocker, may be used to decrease vasospasm but is not known to prevent ventricular remodeling. Metoprolol (Lopressor) is a β-adrenergic blocker that inhibits sympathetic nervous stimulation of the heart.


When instructing the patient with angina about taking sublingual nitroglycerin tablets, what should the nurse teach the patient?

a. To lie or sit and place one tablet under the tongue when chest pain occurs

b. To take the tablet with a large amount of water so it will dissolve right away

c. That if one tablet does not relieve the pain in 15 minutes, the patient should go to the hospital

d. That if the tablet causes dizziness and a headache, stop the medication and call the doctor or go to the hospital


A common complication of nitrates is dizziness caused by orthostatic hypotension, so the patient should sit or lie down and place the tablet under the tongue. The tablet should be allowed to dissolve under the tongue. To prevent the tablet from being swallowed, water should not be taken with it. The recommended dose for the patient for whom nitroglycerin (NTG) has been prescribed is one tablet taken sublingually (SL) or one metered spray for symptoms of angina. If symptoms are unchanged or worse after 5 minutes, the patient should contact the emergency medical services (EMS) system before taking additional NTG. If symptoms are significantly improved by one dose of NTG, instruct the patient or caregiver to repeat NTG every 5 minutes for a maximum of three doses and contact EMS if symptoms have not resolved completely. Headache is also a common complication of nitrates but usually resolves with continued use of nitrates and may be controlled with mild analgesics.


When teaching an older adult with CAD how to manage the treatment program for angina, which guidelines does the nurse use to teach the patient?

a. To sit for 2 to 5 minutes before standing when getting out of bed

b. To exercise only twice a week to avoid unnecessary strain on the heart

c. That lifestyle changes are not as necessary as they would be in a younger person

d. That aspirin therapy is contraindicated in older adults because of the risk for bleeding


Orthostatic hypotension may cause dizziness and falls in older adults taking antianginal agents that decrease preload. Patients should be cautioned to change positions slowly. Daily exercise programs are indicated for older adults and may increase performance, endurance, and ability to tolerate stress. A change in lifestyle behaviors may increase the quality of life and reduce the risks of CAD, even in the older adult. Aspirin is commonly used in these patients and is not contraindicated


When a patient reports chest pain, why must unstable angina be identified and rapidly treated?

a. The pain may be severe and disabling.

b. ECG changes and dysrhythmias may occur during an attack.

c. Rupture of unstable plaque may cause complete thrombosis of the vessel lumen

d. Spasm of a major coronary artery may cause total occlusion of the vessel with progression to MI

c. Rupture of unstable plaque may cause complete thrombosis of the vessel lumen

Rational: Unstable angina is associated with the rupture of a once-stable atherosclerotic plaque, exposing the intima to blood and stimulating platelet aggregation and local vasoconstriction with thrombus formation. Patients with unstable angina require immediate hospitalization and monitoring because the lesion is at increased risk of complete thrombosis of the lumen with progression to MI. Any type of angina may be associated with severe pain, ECG changes, and dysrhythmias. Prinzmetal's angina is characterized by coronary artery spasm


The nurse suspects stable angina rather than MI pain in the patient who reports that his chest pain

a. is relieved by nitroglycerin.

b. is a sensation of tightness or squeezing.

c. does not radiate to the neck, back, or arms.

d. is precipitated by physical or emotional exertion.


One of the primary differences between the pain of angina and the pain of an MI is that angina pain is usually relieved by rest or nitroglycerin, which reduces the oxygen demand of the heart, whereas MI pain is not. Both angina and MI pain can cause a pressure or squeezing sensation; may or may not radiate to the neck, back, arms, fingers, and jaw; and may be precipitated by exertion


A patient admitted to the hospital for evaluation of chest pain has no abnormal serum cardiac markers 4 hours after the onset of pain. What noninvasive diagnostic test can be used to differentiate angina from other types of chest pain?

a. 12-lead ECG

b. Exercise stress test

c. Coronary angiogram

d. Transesophageal echocardiogram


An exercise stress test will reveal ECG changes that indicate impaired coronary circulation when the oxygen demand of the heart is increased. A single ECG is not conclusive for CAD and negative findings do not rule out CAD. Coronary angiography can detect narrowing of coronary arteries but is an invasive procedure. Echocardiograms of various types may identify abnormalities of myocardial wall motion under stress but are indirect measures of CAD


A 52-year-old man is admitted to the emergency department with severe chest pain. On what basis would the nurse suspect an MI?

a. He has pale, cool, clammy skin.

b. He reports nausea and vomited once at home.

c. He says he is anxious and has a feeling of impending doom.

d. He reports he has had no relief of the pain with rest or position change.


The subjective report of the pain from an MI is usually severe. It usually is unrelieved by nitroglycerin, rest, or position change and usually lasts more than the 15 or 20 minutes typical of angina pain. All of the other symptoms may occur with angina as well as with an MI


At what point in the healing process of the myocardium following an infarct does early scar tissue result in an unstable heart wall?

a. 2 to 4 days after MI

b. 4 to 10 days after MI

c. 10 to 14 days after MI

d. 6 weeks after MI


At 10 to 14 days after MI, the myocardium is considered especially vulnerable to increased stress because of the unstable state of healing at this point, as well as the increasing physical activity of the patient. At 2 to 4 days, removal of necrotic tissue is taking place by phagocytic cells. By 4 to 10 days, the necrotic tissue has been cleared and a collagen matrix for scar tissue has been deposited. Healing with scar-tissue replacement of the necrotic area is usually complete by 6 weeks


To detect and treat the most common complication of MI, what should the nurse do?

a. Measure hourly urine output.

b. Auscultate the chest for crackles.

c. Use continuous cardiac monitoring.

d. Take vital signs every 2 hours for the first 8 hours.


The most common complication of MI is cardiac dysrhythmias. Continuous cardiac monitoring allows identification and treatment of dysrhythmias that may cause further deterioration of the cardiovascular status or death. Measurement of hourly urine output and vital signs is indicated to detect symptoms of the complication of cardiogenic shock. Crackles, dyspnea, and tachycardia may indicate the onset of heart failure


During the assessment, the nurse identifies crackles in the lungs and an S3 heart sound. Which complication of MI should the nurse suspect and further investigate?

a. Pericarditis

b. Heart failure

c. Ventricular aneurysm

d. Papillary muscle dysfunction


Left sided heart failure, which can escalate to cardiogenic shock, initially occurs and manifests as mild dyspnea, restlessness, agitation, pulmonary congestion with crackles, S3 or S4 heart sounds. Right sided HF includes jugular vein distention, hepatic congestion, or lower extremety edema. Pericarditis is a common complication identified with chest pain that is aggravated by inspiration, coughing, and moving the upper body. Ventricular aneurysm is manifested with heart failure, dysrhythmias, and angina. Papillary muscle dysfunction is suspected with a new systolic apical murmur


In the patient with chest pain, which results can differentiate unstable angina from an MI?

a. ECG changes present at the onset of the pain

b. A chest x-ray indicating left ventricular hypertrophy

c. Serum toponin levels increased 4 to 6 hours after the onset

d. Creatine kinase (CK)-MB enzyme elevations that peak 6 hours after the infarct


Cardiac specific troponin T and troponin I have greater sensitivity and specificity for myocardial injury than creatine kinase MB (CK-MB), are released 4 to 6 hours after the onset of MI, peak in 10-24 hours, and returns to baseline over 10-14 days. CK-MB levels begin to rise 6 hours after an acute MI, peak in about 18 hours, and return to normal within 24 to 36 hours. ECG changes are often not apparent immediately after infarct and may be normal when the patient seeks medical attention. An enlarged heart, determined by x-ray, indicates cardiac stress but is not diagnostic of acute MI


A second 12-lead ECG performed on a patient 4 hours after the onset of chest pain reveals ST segment elevation. What does the nurse recognize that this finding indicates?

a. Transient ischemia typical of unstable angina

b. Lack of permanent damage to myocardial cells

c. MI associated with prolonged and complete coronary thrombosis

d. MI associated with transient or incomplete coronary artery occlusion


A differentiation is made between MIs that have ST segment elevations on ECG and those that do not because chest pain accompanied by ST segment elevations is associated with prolonged and complete coronary thrombosis and is treated with reperfusion therapy. The other options are incorrect.