MI

Question 1

The patient is admitted with a suspected acute myocardial infarction (MI). In assessing the 12-lead electrocardiogram (ECG) changes, which findings would indicate to the nurse that the patient is in the process of an evolving Q wave myocardial infarction(MI)?

a. ST-segment elevation on ECG and elevated CPK-MB or troponin levels
b. Depressed ST-segment on ECG and elevated total CPK
c. Depressed ST-segment on ECG and normal cardiac enzymes
d. Q wave on ECG with normal enzymes and troponin levels

Answer 1

ANS: A

ST segment elevation and elevated cardiac enzymes are seen in Q wave MI.

Question 2

A patient presents to the emergency department (ED) with chest pain that he has had for the past 2 hours. He is nauseous and diaphoretic, and his skin is dusky in color. The electrocardiogram shows ST elevation in leads II, III, and aVF. Which therapeutic intervention would the nurse question?

a. Emergent pacemaker insertion
b. Emergent percutaneous coronary intervention
c. Emergent thrombolytic therapy
d. Immediate coronary artery bypass graft surgery

Answer 2

ANS: A
The goals of management of AMI are to dissolve the lesion that is occluding the coronary artery and to increase blood flow to the myocardium. Options include emergent percutaneous intervention, such as angioplasty, emergent coronary artery bypass graft surgery, or thrombolytic therapy if the patient has been symptomatic for less than 6 hours. No data in this scenario warrant insertion of a pacemaker.

Question 3

While instructing a patient on what occurs with a myocardial infarction, the nurse plans to explain which process?

a. Coronary artery spasm.
b. Decreased blood flow (ischemia).
c. Death of cardiac muscle from lack of oxygen (tissue necrosis).
d. Sporadic decrease in oxygen to the heart (transient oxygen imbalance).

Answer 3

ANS: C

Acute myocardial infarction is death (tissue necrosis) of the myocardium that is caused by lack of blood supply from the occlusion of a coronary artery and its branches.

Question 4

The nurse is examining the ECG of a patient who has just been admitted with a suspected myocardial infarction (MI). Which ECG change is most indicative of prolonged or complete coronary occlusion?
1 Sinus tachycardia
2Pathologic Q wave
3Fibrillatory P waves
4Prolonged PR interva

Answer 4

ANS: 2
The presence of a pathologic Q wave, which often accompanies ST segment elevation myocardial infarction (STEMI), is indicative of complete coronary occlusion. Sinus tachycardia, fibrillatory P waves (e.g., atrial fibrillation), or a prolonged PR interval (first-degree heart block) are not direct indicators of extensive occlusion.

Question 5

A patient with three-vessel coronary artery disease has a random blood sugar level of 197 mg/dL. The laboratory reports show the presence of cardiac-specific troponin I (cTnI) and cardiac-specific troponin T (cTnT) markers. The nurse identifies that which intervention will benefit the patient?
1 Placement of drug-eluting stents
2 Coronary surgical revascularization
3Percutaneous coronary intervention
4Intraaortic balloon pump (IABP) therapy

Answer 5

ANS: 2
Coronary surgical revascularization helps restore the blood flow to the heart by replacing new blood vessels around existing blockages. This procedure is best for a patient with diabetes and three-vessel disease, because it helps improve perfusion to the myocardial muscle. A patient with confirmed myocardial infarction needs the placement of drug-eluting stents via cardiac catheterization. Percutaneous coronary intervention is a first line of treatment for a patient with definitive electrocardiogram changes and positive cardiac markers. Intraaortic balloon pump (IABP) therapy is used to treat severe left ventricular dysfunction.

Question 6

A patient is recovering from an uncomplicated myocardial infarction (MI). Which instructions will the nurse include when discussing physical activity?
1”Start out with 30-minute sessions.”
2”Be sure to perform physical activity at least twice a week.”
3”Physical activity should be regular, rhythmic, and repetitive.”
4”Your heart rate during exercise should only go up to 30 beats over your resting heart rate.

Answer 6

ANS: 3
Physical activity should be regular, rhythmic, and repetitive, using large muscles to build up endurance (e.g., walking, cycling, swimming, rowing). Physical activity sessions should be at least 30 minutes long. Instruct the patient to begin slowly at personal tolerance (perhaps only 5 to 10 minutes) and build up to 30 minutes. Encourage the patient to perform physical activity on most days of the week. Activity intensity is determined by the patient’s heart rate. If an exercise stress test has not been performed, the heart rate of the patient recovering from an MI should not exceed 20 beats/minute over the resting heart rate.

Question 7

A patient reports heaviness and burning sensation in the substernal and retrosternal region. Assessment findings include a fasting blood glucose of 190 mg/dL and blood pressure of 145/90 mm Hg. The nurse recognizes that which other finding indicates sympathetic nervous system stimulation?
1 Jugular venous distention
2 Abnormal S3 and S4 sounds
3 Ashen, clammy, and cool skin
4 Shortness of breath and anxiety

Answer 7

ANS: 3
A patient with heaviness and burning sensation in the substernal and retrosternal region may be having a myocardial infarction (MI) and stimulation of the sympathetic nervous system. This condition may trigger the production of catecholamines, which promote glycogen release, diaphoresis, and vasoconstriction of peripheral blood vessels. Because of this, the patient’s skin may appear ashen, clammy, and cool to the touch. Jugular vein distention and abnormal S3 and S4 sounds are caused by ventricular dysfunction. Shortness of breath and anxiety may not necessarily be caused by sympathetic nervous system stimulation.

Question 8

The nurse assesses a patient with diabetes who reports shortness of breath, neck pain, and hypoglycemic symptoms. The patient’s blood pressure is 130/86 mm Hg, heart rate is 102 beats/minute, respiratory rate is 24 breaths/minute, and the fingerstick blood glucose is 136 mg/dL. The nurse recognizes that the patient may be experience
1 Myocardial infarction
2 Late-stage diabetic ketoacidosis
3 Early-onset diabetic ketoacidosis
4 Hyperosmolar hyperglycemic nonketotic syndrome

Answer 8

ANS: 1
Signs and symptoms of a myocardial infarction (MI) include shortness of breath, neck pain, and cool, clammy skin. Although cool, clammy skin may resemble a hypoglycemic reaction, when found along with shortness of breath and neck pain it is very specific for an MI. The patient is not experiencing a complication of diabetes (ketoacidosis or hyperosmolar hyperglycemic nonketotic syndrome). The blood glucose is close to normal, and further diagnostics would be required to determine a diabetic complication. Only cool, clammy skin is indicative of hypoglycemia.

Question 9

During the 48 hours after a myocardial infarction, a nurse should assign the highest priority to monitoring the patient for:
1 Dysrhythmias
2 Anxiety and fear
3 Metabolic acidosis
4 Medication side effects

Answer 9

ANS: 1
The nurse must be most alert for dysrhythmias, which may signal another MI or impending complications. The nurse should also be alert for increased anxiety, which may cause pain and lead to a secondary infarction. Anxiety and fear are highly likely but secondary in importance to monitoring the patient for dysrhythmias. Metabolic acidosis and reactions to new medications are not likely but should still be included as part of overall assessment of the patient.

Question 10

Postoperative care of a patient undergoing coronary artery bypass graft (CABG) surgery includes monitoring for what common complication?
1 Dehydration
2 Paralytic ileus
3 Atrial dysrhythmias
4 Acute respiratory distress syndrome

Answer 10

ANS:C
Postoperative dysrhythmias, specifically atrial dysrhythmias, are common in the first three days following CABG surgery. Although dehydration, paralytic ileus, and acute respiratory distress syndrome could occur, they are not common complications.

Question 11

For which problem is percutaneous coronary intervention (PCI) most clearly indicated?
1 Chronic stable angina
2 Left-sided heart failure
3Coronary artery disease (CAD)
4Acute myocardial infarction

Answer 11

ANS: 4
PCI is indicated to restore coronary perfusion in cases of myocardial infarction. Chronic stable angina and CAD normally are treated with more conservative measures initially. PCI is not relevant to the pathophysiology of heart failure, such as left-sided heart failure.

Question 12

The nurse reviews the prescriptions for cardiac markers for a patient who is suspected of having a myocardial infarction (MI). Because of its limited use in diagnosing an MI, the prescription for which cardiac marker should be questioned by the nurse?
1 Myoglobin
2Creatine kinase-MB (CKMB)
3Cardiac-specific troponin I (cTnI)
4Cardiac-specific troponin T (cTnT)

Answer 12

ANS: 1
Myoglobin is a serum cardiac marker that is released into the circulation two hours after a myocardial infarction (MI). Myoglobin’s role in diagnosing MI is limited because it lacks cardiac specificity. Creatine kinase-MB (CKMB) levels begin to rise about six hours after MI, are specific to myocardial cells, and help quantify myocardial damage. Cardiac-specific troponin T (cTnT) and cardiac-specific troponin I (cTnI) are highly specific indicators of MI.

Question 13

The nurse assesses a patient who has been administered the tissue-type plasminogen activator alteplase for an acute myocardial infarction. Which assessment finding is the highest priority and should be reported to the primary health care provider immediately?
1 Anorexia
2 Hematuria
3 Oral temperature of 100.4° F (38° C)
4 Occasional premature ventricular contractions

Answer 13

ANS: 2
Alteplase is a proteolytic enzyme that digests threads and other substances in the blood, including clotting factors, thereby causing hypercoagulability of the blood and possibly bleeding, which is evidenced by blood in the urine. Anorexia and increased temperature are not issues directly related to this drug. Alteplase may cause premature ventricular contractions, which should be monitored, but this is usually not a problem because the drug has a short half-life.

Question 14

A patient was admitted to the emergency department (ED) 24 hours earlier with complaints of chest pain that subsequently were attributed to ST segment elevation myocardial infarction (STEMI). What complication of myocardial infarction (MI) should the nurse anticipate?
1 Unstable angina
2 Cardiac tamponade
3 Sudden cardiac death
4 Cardiac dysrhythmias

Answer 14

ANS: 4
The most common complication after MI is dysrhythmias, which are present in 80 percent of patients. Unstable angina is considered a precursor to MI rather than a complication. Cardiac tamponade is a rare event, and sudden cardiac death is defined as an unexpected death from cardiac causes. Cardiac dysfunction in the period following an MI would not be characterized as sudden cardiac death.

Question 15

Heart disease in women is manifested by a variety of subtle signs. Which sign is typically seen in women?

a. Fainting
b. Chest pain
c. Dizziness
d. Fatigue

Answer 15

ANS: D
Women frequently experience fatigue with heart disease. Many women do not even experience chest pain. Fainting and dizziness are not typical signs of heart disease in women.

Question 16

The drug alteplase (t-PA) is given to the patient with a myocardial infarction (MI). The nurse is aware the drug will:

a. dissolve the obstruction in the coronary artery.
b. dilate vessels to relieve pain.
c. strengthen cardiac contraction.
d. increase cardiac output.

Answer 16

ANS: A

Alteplase (t-PA) is a thrombolytic drug that will dissolve the clot if given within 12 hours of the MI.

Question 17

The nurse counsels a patient that the administration of thrombolytic drugs would be contraindicated in the patient who is:

a. hypotensive.
b. being treated for a bleeding ulcer.
c. presently taking warfarin (Coumadin).
d. prone to asthma attacks.

Answer 17

ANS: B
Thrombolytic agents are contraindicated in people with uncontrolled hypertension, GI bleeds, recent intracranial or intraspinal surgery, or aneurysm because of threat of excessive bleeding.

Question 18

Following a cardiac catheterization with coronary angiography, the physician writes an order to increase the patients fluid intake. The nurse knows that increasing the fluid intake is ordered for what reason?

a. Reducing the nausea related to the dye absorption
b. Maintaining adequate blood pressure and perfusion
c. Diluting the urine to prevent kidney damage
d. Making up for fluid lost during the angiogram

Answer 18

ANS: C
The dye used in a cardiac catheterization with coronary angiography is excreted through the kidneys and may cause damage to the kidneys. Fluid is encouraged to dilute urine to prevent kidney damage

Question 19

The patient in the emergency room with a myocardial infarction (MI) becomes pale, diaphoretic, and hypotensive and complains of feeling cold. The nurse recognizes that these signs are which post-MI complication?

a. Cardiogenic shock
b. Pleural effusion
c. Ventricular fibrillation
d. Pulmonary embolus

Answer 19

ANS: A

Cardiogenic shock is characterized by all the signs mentioned. Cardiogenic shock is a medical emergency.

Question 20

Following patient teaching regarding a scheduled minimally invasive direct coronary artery bypass (MIDCAB), the nurse determines the need for further instruction when the patient makes which statement?

a. It frightens me to think that my heart will be stopped during surgery.
b. This surgery bypasses my artery that is blocked, and replaces it with sections of a vein or artery taken from another part of my body.
c. This surgery will hopefully control my angina since nothing else we have tried has worked.
d. I may come out of surgery with vessels removed from my legs.

Answer 20

ANS: A
The MIDCAB procedure is less invasive than the traditional coronary artery bypass graft (CABG) procedure and does not require the patient be placed on the heart-lung machine due to stopping the heart for an extended period. Both procedures are used to treat angina that has not responded to more conservative treatment and utilize either the mammary artery or sections of the saphenous vein for the graft.

Question 21

The nurse is aware that a positive diagnosis of a myocardial infarction (MI) is based on which diagnostic test results? (Select all that apply.)

a. Electrocardiographic (ECG) changes in the QRS complex
b. Elevation of low-density lipoprotein (LDH)
c. Elevation of troponin levels
d. Elevated white blood cell (WBC) count
e. Elevated T wave

Answer 21

ANS: A, C, E
Elevation of enzymes and altered QRS patterns are positive for diagnosis of MI. Elevation of T wave and WBC count, although present, are not specific to MI formation.

Question 22

Which information collected by the nurse who is admitting a patient with chest pain suggests that the pain is caused by an acute myocardial infarction (AMI)?

a. The pain increases with deep breathing.
b. The pain has persisted longer than 30 minutes.
c. The pain worsens when the patient raises the arms.
d. The pain is relieved after the patient takes nitroglycerin.

Answer 22

ANS: B
Chest pain that lasts for 20 minutes or more is characteristic of AMI. Changes in pain that occur with raising the arms or with deep breathing are more typical of pericarditis or musculoskeletal pain. Stable angina is usually relieved when the patient takes nitroglycerin.

Question 23

After the nurse has finished teaching a patient about use of sublingual nitroglycerin (Nitrostat), which patient statement indicates that the teaching has been effective?

a. I can expect indigestion as a side effect of nitroglycerin.
b. I can only take the nitroglycerin if I start to have chest pain.
c. I will call an ambulance if I still have pain 5 minutes after taking the nitroglycerin.
d. I will help slow down the progress of the plaque formation by taking nitroglycerin.

Answer 23

ANS: C
The emergency medical services (EMS) system should be activated when chest pain or other symptoms are not completely relieved 5 minutes after taking one nitroglycerin. Nitroglycerin can be taken to prevent chest pain or other symptoms from developing (e.g., before intercourse). Gastric upset is not an expected side effect of nitroglycerin. Nitroglycerin does not impact the underlying pathophysiology of coronary artery atherosclerosis.

Question 24

A patient with a nonST-segment-elevation myocardial infarction (NSTEMI) is receiving heparin. What is the purpose of the heparin?

a. Platelet aggregation is enhanced by IV heparin infusion.
b. Heparin will dissolve the clot that is blocking blood flow to the heart.
c. Coronary artery plaque size and adherence are decreased with heparin.
d. Heparin will prevent the development of new clots in the coronary arteries.

Answer 24

ANS: D
Heparin helps prevent the conversion of fibrinogen to fibrin and decreases coronary artery thrombosis. It does not change coronary artery plaque, dissolve already formed clots, or enhance platelet aggregation.

Question 25

When administering IV nitroglycerin (Tridil) to a patient with a myocardial infarction (MI), which action will the nurse take to evaluate the effectiveness of the medication?

a. Check blood pressure.
b. Monitor apical pulse rate.
c. Monitor for dysrhythmias.
d. Ask about chest discomfort.

Answer 25

ANS: D
The goal of IV nitroglycerin administration in MI is relief of chest pain by improving the balance between myocardial oxygen supply and demand. The nurse also will monitor heart rate and BP and observe for dysrhythmias, but these parameters will not indicate whether the medication is effective.

Question 26

A patient with ST segment elevation in several electrocardiographic (ECG) leads is admitted to the emergency department (ED) and diagnosed as having an ST-segment-elevation myocardial infarction (STEMI). Which question should the nurse ask to determine whether the patient is a candidate for fibrinolytic therapy?

a. Do you take aspirin on a daily basis?
b. What time did your chest pain begin?
c. Is there any family history of heart disease?
d. Can you describe the quality of your chest pain?

Answer 26

ANS: B
Fibrinolytic therapy should be started within 6 hours of the onset of the myocardial infarction (MI), so the time at which the chest pain started is a major determinant of the appropriateness of this treatment. The other information also will be needed, but it will not be a factor in the decision about fibrinolytic therapy.

Question 27

Following an acute myocardial infarction (AMI), a patient ambulates in the hospital hallway. When the nurse is evaluating the patients response, which of these assessment data would indicate that the exercise level should be decreased?

a. BP changes from 118/60 to 126/68 mm Hg.
b. Oxygen saturation drops from 100% to 98%.
c. Heart rate increases from 66 to 90 beats/minute.
d. Respiratory rate goes from 14 to 22 breaths/minute.

Answer 27

ANS: C
A change in heart rate of more than 20 beats or more indicates that the patient should stop and rest. The increases in BP and respiratory rate, and the slight decrease in oxygen saturation, are normal responses to exercise.

Question 28

During the administration of the fibrinolytic agent to a patient with an acute myocardial infarction (AMI), the nurse should stop the drug infusion if the patient experiences

a. bleeding from the gums.
b. surface bleeding from the IV site.
c. a decrease in level of consciousness.
d. a nonsustained episode of ventricular tachycardia.

Answer 28

ANS: C
The change in level of consciousness indicates that the patient may be experiencing intracranial bleeding, a possible complication of fibrinolytic therapy. Bleeding of the gums and prolonged bleeding from IV sites are expected side effects of the therapy. The nurse should address these by avoiding any further injuries, but they are not an indication to stop infusion of the fibrinolytic medication. A nonsustained episode of ventricular tachycardia is a common reperfusion dysrhythmia and may indicate that the therapy is effective.

Question 29

After the nurse teaches a patient with chronic stable angina about how to use the prescribed short-acting and long-acting nitrates, which statement by the patient indicates that the teaching has been effective?

a. I will put on the nitroglycerin patch as soon as I develop any chest pain.
b. I will check the pulse rate in my wrist just before I take any nitroglycerin.
c. I will be sure to remove the nitroglycerin patch before using any sublingual nitroglycerin.
d. I will stop what I am doing and sit down before I put the nitroglycerin under my tongue.

Answer 29

ANS: D
The patient should sit down before taking the nitroglycerin to decrease cardiac workload and prevent orthostatic hypotension. Transdermal nitrates are used prophylactically rather than to treat acute pain and can be used concurrently with sublingual nitroglycerin. Although the nurse should check blood pressure before giving nitroglycerin, patients do not need to check the pulse rate before taking nitrates.

Question 30

Four days after having a myocardial infarction (MI), a patient who is scheduled for discharge asks for assistance with all the daily activities, saying, I am too nervous to take care of myself. Based on this information, which nursing diagnosis is appropriate?

a. Ineffective coping related to anxiety
b. Activity intolerance related to weakness
c. Denial related to lack of acceptance of the MI
d. Social isolation related to lack of support system

Answer 30

ANS: A
The patient data indicates that ineffective coping after the MI caused by anxiety about the impact of the MI is a concern. The other nursing diagnoses may be appropriate for some patients after an MI, but the data for this patient do not support denial, activity intolerance, or social isolation.

Question 31

When evaluating the outcomes of preoperative teaching with a patient scheduled for a coronary artery bypass graft (CABG) using the internal mammary artery, the nurse determines that additional teaching is needed when the patient says,

a. I will have incisions in my leg where they will remove the vein.
b. They will circulate my blood with a machine during the surgery.
c. I will need to take an aspirin a day after the surgery to keep the graft open.
d. They will use an artery near my heart to bypass the area that is obstructed.

Answer 31

ANS: A
When the internal mammary artery is used there is no need to have a saphenous vein removed from the leg. The other statements by the patient are accurate and indicate that the teaching has been effective.

Question 32

A patient who has had an acute myocardial infarction (AMI) asks the nurse about when sexual intercourse can be resumed. Which response by the nurse is best?

a. Most patients are able to enjoy intercourse without any complications.
b. Sexual activity uses about as much energy as climbing two flights of stairs.
c. The doctor will discuss sexual intercourse when your heart is strong enough.
d. Holding and cuddling are good ways to maintain intimacy after a heart attack.

Answer 32

ANS: B
Sexual activity places about as much physical stress on the cardiovascular system as climbing two flights of stairs. The other responses do not directly address the patients question, or may not be accurate for this patient.

Question 33

Which assessment finding by the nurse who is caring for a patient who has had coronary artery bypass grafting using a right radial artery graft is most important to communicate to the physician?

a. Complaints of incisional chest pain
b. Crackles audible at both lung bases
c. Pallor and weakness of the right hand
d. Redness on either side of the chest incision

Answer 33

ANS: C
The changes in the right hand indicate compromised blood flow, which requires immediate evaluation and actions such as prescribed calcium channel blockers or surgery. The other changes are expected and/or require nursing interventions.

Question 34

When caring for a patient with acute coronary syndrome who has returned to the coronary care unit after having balloon angioplasty, the nurse obtains the following assessment data. Which data indicate the need for immediate intervention by the nurse?

a. Pedal pulses 1+
b. Heart rate 100 beats/min
c. Blood pressure 104/56 mm Hg
d. Chest pain level 8 on a 10-point scale

Answer 34

ANS: D
The patients chest pain indicates that restenosis of the coronary artery may be occurring and requires immediate actions, such as administration of oxygen and nitroglycerin, by the nurse. The other information indicates a need for ongoing assessments by the nurse.

Question 35

A patient admitted to the coronary care unit (CCU) with an ST-segment-elevation myocardial infarction (STEMI) is restless and anxious. The blood pressure is 86/40 and heart rate is 110. Based on this information, which nursing diagnosis is a priority for the patient?

a. Acute pain related to myocardial ischemia
b. Anxiety related to perceived threat of death
c. Decreased cardiac output related to cardiogenic shock
d. Activity intolerance related to decreased cardiac output

Answer 35

ANS: C
All the nursing diagnoses may be appropriate for this patient, but the hypotension indicates that the priority diagnosis is decreased cardiac output, which will decrease perfusion to all vital organs (e.g., brain, kidney, heart).

Question 36

When admitting a patient with a myocardial infarction (MI) to the intensive care unit, which action should the nurse carry out first?

a. Obtain the blood pressure.
b. Attach the cardiac monitor.
c. Assess the peripheral pulses.
d. Auscultate the breath sounds.

Answer 36

ANS: B
Because dysrhythmias are the most common complication of MI, the first action should be to place the patient on a cardiac monitor. The other actions also are important and should be accomplished as quickly as possible.

Question 37

Which information about a patient who has been receiving fibrinolytic therapy for an acute myocardial infarction (AMI) is most important for the nurse to communicate to the health care provider?

a. No change in the patients chest pain
b. A large bruise at the patients IV insertion site
c. A decrease in ST segment elevation on the electrocardiogram (ECG)
d. An increase in cardiac enzyme levels since admission

Answer 37

ANS: A
Continued chest pain suggests that the fibrinolytic therapy is not effective and that other interventions such as percutaneous coronary intervention (PCI) may be needed. Bruising is a possible side effect of fibrinolytic therapy, but it is not an indication that therapy should be discontinued. The decrease of the ST segment elevation indicates that fibrinolysis is occurring and perfusion is returning to the injured myocardium. An increase in cardiac enzyme levels is expected with reperfusion and is related to the washout of enzymes into the circulation as the blocked vessel is opened.

Question 38

The nurse obtains the following data when caring for a patient who experienced an acute myocardial infarction (AMI) 2 days previously. Which information is most important to report to the health care provider?

a. The patient denies ever having a heart attack.
b. The cardiac-specific troponin level is elevated.
c. The patient has occasional premature atrial contractions (PACs).
d. Crackles are auscultated bilaterally in the mid-lower lobes.

Answer 38

ANS: D
The crackles indicate that the patient may be developing heart failure, a possible complication of myocardial infarction (MI). The health care provider may need to order medications such as diuretics or angiotensin-converting enzyme (ACE) inhibitors for the patient. Elevation in cardiac troponin level at this time is expected. PACs are not life-threatening dysrhythmias. Denial is a common response in the immediate period after the MI.

Question 39

A patient who has chest pain is admitted to the emergency department (ED), and all the following diagnostic tests are ordered. Which one will the nurse arrange to be completed first?

a. Electrocardiogram (ECG)
b. Computed tomography (CT) scan
c. Chest x-ray
d. Troponin level

Answer 39

ANS: A
The priority for the patient is to determine whether an acute myocardial infarction (AMI) is occurring so that reperfusion therapy can begin as quickly as possible. ECG changes occur very rapidly after coronary artery occlusion. Troponin levels will increase after about 3 hours. Data from the CT scan and chest x-ray may impact the patients care but are not helpful in determining whether the patient is experiencing a myocardial infarction (MI).

Question 40

The nurse has just received change-of-shift report about the following four patients. Which patient should the nurse assess first?

a. 38-year-old who has pericarditis and is complaining of sharp, stabbing chest pain
b. 45-year-old who had a myocardial infarction (MI) 4 days ago and is anxious about the planned discharge
c. 51-year-old with unstable angina who has just returned to the unit after having a percutaneous coronary intervention (PCI)
d. 60-year-old with variant angina who is to receive a scheduled dose of nifedipine (Procardia)

Answer 40

ANS: C
This patient is at risk for bleeding from the arterial access site for the PCI, so the nurse should assess the patients blood pressure, pulse, and the access site immediately. The other patients also should be assessed as quickly as possible, but assessment of this patient has the highest priority

Question 41

A 66-year-old patient is admitted to the critical care unit with a diagnosis of acute inferior MI. A 12-lead electrocardiogram (ECG) is done to validate the area of infarction. Which finding on the ECG is most conclusive for infarction?

a. Inverted T waves
b. Tall, peaked T waves
c. ST segment depression
d. Pathologic Q waves

Answer 41

ANS: D
The changes in repolarization are seen by the presence of new Q waves. These new, pathologic Q waves are deeper and wider than tiny Q waves found on the normal 12-lead ECG.

Question 42

A 66-year-old patient is admitted to the critical care unit with a diagnosis of acute inferior MI. A 12-lead electrocardiogram (ECG) is done to validate the area of infarction. For the above patient, which leads on the ECG would correlate with an inferior wall MI?

a. II, III, aVF
b. V5 to V6, I, aVL
c. V2 to V4
d. V1 to V2

Answer 42

ANS: A
Inferior infarctions are manifested by electrocardiographic (ECG) changes in leads II, III, and aVF. Lateral wall infarctions are manifested by ECG changes in leads V5 to V6, I, and aVL. Anterior wall infarctions are manifested by ECG changes in leads V2 to V4. Posterior wall infarctions are manifested by ECG changes in leads V1 to V2.

Question 43

Which classification of dysrhythmia is most common with an inferior wall infarction in the first hour after STEMI?

a. Sinus tachycardia
b. Multifocal PVCs
c. Atrial fibrillation
d. Sinus bradycardia

Answer 43

ANS: D
Sinus bradycardia (heart rate less than 60 beats/min) occurs in 30% to 40% of patients who sustain an acute myocardial infarction (MI). It is more prevalent with an inferior wall infarction in the first hour after ST segment elevation MI. Sinus tachycardia (heart rate more than 100 beats/min) most often occurs with an anterior wall MI. Premature atrial contractions (PACs) occur frequently in patients who sustain an acute MI. Atrial fibrillation is also common and may occur spontaneously or may be preceded by PACs. Premature ventricular contractions (PVCs) are seen in almost all patients within the first few hours after an MI.

Question 44

Which of the following are mechanisms responsible for a myocardial infarction (MI)? (Select all that apply.)

a. Coronary artery thrombosis
b. Plaque rupture
c. Coronary artery spasm near the ruptured plaque
d. Preinfarction angina
e. Hyperlipidemia

Answer 44

ANS: A, B, C
The three mechanisms that block the coronary artery and are responsible for the acute reduction in oxygen delivery to the myocardium are (1) plaque rupture, (2) new coronary artery thrombosis, and (3) coronary artery spasm close to the ruptured plaque.