Myocardial Infarction

Question 1

What is the New York Heart Association Functional

Classification of Cardiovascular Disability?

Answer 1

It is a classification system that stratifies patients based on the
severity of coronary ischemia-related symptoms. It is divided
into Classes I, II, III, and IV.
Nagelhout JJ, Plaus KL. Nurse Anesthesia. 5th ed. St. Louis,
MO: Elsevier Saunders Company; 2014: 354.

Question 2

What is the definition of a Class I patient according
to the New York Heart Association Functional
Classification of Cardiovascular Disability?

Answer 2

A patient that has cardiac disease but has no limitations in
functional ability and no symptoms that occur during normal
activity.
Nagelhout JJ, Plaus KL. Nurse Anesthesia. 5th ed. St. Louis,
MO: Elsevier Saunders Company; 2014: 354.

Question 3

What is the definition of a Class II patient according
to the New York Heart Association Functional
Classification of Cardiovascular Disability?

Answer 3

A patient who has cardiac disease and does not experience
symptoms at rest. Ordinary physical activity such as climbing
stairs rapidly or emotional stress may produce angina, dyspnea,
fatigue, or palpitation.
Nagelhout JJ, Plaus KL. Nurse Anesthesia. 5th ed. St. Louis,
MO: Elsevier Saunders Company; 2014: 354.

Question 4

What is the definition of a Class III patient according
to the New York Heart Association Functional
Classification of Cardiovascular Disability?

Answer 4

A patient whose cardiac disease markedly limits their activity.
They are comfortable at rest, but even slight activity can
produce ischemic symptoms.
Nagelhout JJ, Plaus KL. Nurse Anesthesia. 5th ed. St. Louis,
MO: Elsevier Saunders Company; 2014: 354.

Question 5

What is the definition of a Class IV patient according
to the New York Heart Association Functional
Classification of Cardiovascular Disability?

Answer 5

A patient who cannot carry on any activity whatsoever without
symptoms and will often experience symptoms of ischemia
even at rest.
Nagelhout JJ, Plaus KL. Nurse Anesthesia. 5th ed. St. Louis,
MO: Elsevier Saunders Company; 2014: 354.

Question 6

What is troponin?

Answer 6

Troponin is a cardiac-specific marker for myocardial infarction
that becomes elevated within 4 hours of myocardial injury and
remains elevated for several days following the event.
Hines RL, Marschall KE. Anesthesia & Co-Existing Diseases.
6th ed. Philadelphia, PA: Elsevier-Saunders; 2012: 8.

Question 7

How do ST depression and ST elevation differ with

regards to the area of ischemia?

Answer 7

Depression of the ST segment is typically associated with
subendocardial ischemia. ST segment elevation is typically
associated with transmural ischemia.
Hines RL, Marschall KE. Anesthesia & Co-Existing Diseases.
6th ed. Philadelphia, PA: Elsevier-Saunders; 2012: 2-3.

Question 8

What are the diagnostic criteria for acute myocardial

infarction?

Answer 8

The diagnosis of an acute MI requires at least two of the
following criteria be met: chest pain, serial cardiac enzymes
indicative of an MI, and an increase and decrease in the cardiac
enzymes.
Hines RL, Marschall KE. Anesthesia & Co-Existing Diseases.
6th ed. Philadelphia, PA: Elsevier-Saunders; 2012: 7.

Question 9

What is unstable angina?

Answer 9

Substernal chest pain that began less than 2 months ago, has
progressively increased in severity, duration, or frequency, is
less responsive to pharmacologic therapy, occurs at rest, lasts
longer than half an hour, or exhibits transient T-wave or ST
segment changes.
Nagelhout JJ, Plaus KL. Nurse Anesthesia. 5th ed. St. Louis,
MO: Elsevier Saunders Company; 2014: 355.

Question 10

What is stable angina?

Answer 10

Stable angina is chest discomfort that is caused by exertion and
relieved by rest and/or nitroglycerin within 15 minutes.
Nagelhout JJ, Plaus KL. Nurse Anesthesia. 5th ed. St. Louis,
MO: Elsevier Saunders Company; 2014: 355.

Question 11

How is unstable angina related to the risk for an

acute MI?

Answer 11

Two-thirds of patients who have had an MI experienced
unstable angina within the 30 days prior to the event.
Hines RL, Marschall KE. Anesthesia & Co-Existing Diseases.
6th ed. Philadelphia, PA: Elsevier-Saunders; 2012: 8.

Question 12

What is the pathophysiology behind a myocardial

infarction?

Answer 12

Myocardial ischemia results from a deficiency in oxygen and
nutrients due to increased demand, decreased supply, or both.
The causative agent is usually coronary artery occlusion from a
thrombus or vasospasm which reduces blood flow to the region
of the myocardium it supplies. Maligant ventricular arrhythmias
may develop as an inadequate collateral circulation fails to
prevent acute ischemia.
Butterworth JF, Mackey DC, Wasnick JD. Morgan & Mikhail’s
Clinical Anesthesiology. 5th ed. New York, NY: McGraw-Hill;
2013: 387.

Question 13

When is drug treatment indicated to reduce

cholesterol levels?

Answer 13

Drug therapy should be initiated when low-density lipoprotein
levels reach 130 mg/dL and should be aimed at reducing it to
less than 100 mg/dL.
Hines RL, Marschall KE. Anesthesia & Co-Existing Diseases.
6th ed. Philadelphia, PA: Elsevier-Saunders; 2012: 4.

Question 14

What is the overall risk for a perioperative MI in the

general population undergoing general anesthesia?

Answer 14

0.3%
Nagelhout JJ, Plaus KL. Nurse Anesthesia. 5th ed. St. Louis,
MO: Elsevier Saunders Company; 2014: 355.

Question 15

How does the risk for perioperative MI compare
between patients with unstable angina and those
with no history of coronary ischemia?

Answer 15

Patients with a history of unstable angina have the highest risk
for perioperative MI. Elective surgery should always be
canceled in these patients until the problem can be definitively
managed.
Nagelhout JJ, Plaus KL. Nurse Anesthesia. 5th ed. St. Louis,
MO: Elsevier Saunders Company; 2014: 355.

Question 16

How does the perioperative risk for MI compare
between patients with stable angina and those with
no history of cardiac symptoms?

Answer 16

There is no significant difference in the perioperative risk of MI.
Nagelhout JJ, Plaus KL. Nurse Anesthesia. 5th ed. St. Louis,
MO: Elsevier Saunders Company; 2014: 355.

Question 17

What are the most common drugs used to treat

angina pectoris?

Answer 17

Antiplatelet drugs, beta-bockers, calcium channel blockers,
nitrates, and angiotensin converting-enzyme inhibitors.
Hines RL, Marschall KE. Anesthesia & Co-Existing Diseases.
6th ed. Philadelphia, PA: Elsevier-Saunders; 2012: 4-6.

Question 18

How does hypertension increase the risk for

coronary ischemia?

Answer 18

It can cause direct vascular damage, left ventricular
hypertrophy, and increased myocardial oxygen demand.
Hines RL, Marschall KE. Anesthesia & Co-Existing Diseases.
6th ed. Philadelphia, PA: Elsevier-Saunders; 2012: 4

Question 19

How long after an MI is the risk for reinfarction the

highest?

Answer 19

The first 30 days after an MI is associated with the highest risk
for reinfarction. The mortality rate with reinfarction is 50%.
Because of these statistics, it is recommended that no patient
undergo elective surgery until at least 4-6 weeks after the MI.
Nagelhout JJ, Plaus KL. Nurse Anesthesia. 5th ed. St. Louis,
MO: Elsevier Saunders Company; 2014: 355.

Question 20

What lifestyle modifications have been shown to

slow the progression of ischemic heart disease?

Answer 20

Smoking cessation, maintaining an ideal body weight, adhering
to a diet low in fat and cholesterol, regular aerobic exercise, and
controlling hypertension.
Hines RL, Marschall KE. Anesthesia & Co-Existing Diseases.
6th ed. Philadelphia, PA: Elsevier-Saunders; 2012: 4.

Question 21

What can occur if nitrates are administered in
patients who have recently taken sildenafil, tadalafil,
or vardenafil?

Answer 21

Severe hypotension may ensue.
Hines RL, Marschall KE. Anesthesia & Co-Existing Diseases.
6th ed. Philadelphia, PA: Elsevier-Saunders; 2012: 5-6.

Question 22

What are the main preoperative evaluation goals for

a patient with a history of ischemic heart disease?

Answer 22

It is important to assess the severity, progression, and
functional limitations the patient experiences. Signs and
symptoms may not be present at rest, so it is important to
question the patient about symptoms that appear during various
levels of activity.
Nagelhout JJ, Plaus KL. Nurse Anesthesia. 5th ed. St. Louis,
MO: Elsevier Saunders Company; 2014: 354-355.

Question 23

What are the most significant risk factors for

ischemic heart disease?

Answer 23

Advanced age, smoking, diabetes melitus, hypertension,
pulmonary disease, previous myocardial infarction, left
ventricular wall motion abnormalities, and peripheral vascular
disease.
Nagelhout JJ, Plaus KL. Nurse Anesthesia. 5th ed. St. Louis,
MO: Elsevier Saunders Company; 2014: 354

Question 24

What is coronary steal?

Answer 24

If an area of the heart becomes ischemic, the release of
metabolic factors from this region will result in vasodilation of
the surrounding, normal myocardium. Blood distributed to the
normal heart will decrease the blood flow to the already
compromised ischemic region through collateral vessels and
further decrease its blood supply.
Nagelhout JJ, Plaus KL. Nurse Anesthesia. 5th ed. St. Louis,
MO: Elsevier Saunders Company; 2014: 93.

Question 25

To what degree must coronary blood flow through an

artery decrease before symptoms appear?

Answer 25

Normally, the patient doesn’t experience symptoms at rest until
the stenotic segment reaches 70% occlusion.
Butterworth JF, Mackey DC, Wasnick JD. Morgan & Mikhail’s
Clinical Anesthesiology. 5th ed. New York, NY: McGraw-Hill;
2013: 388.

Question 26

What are the three components in the treatment of

ischemic heart disease?

Answer 26

Lifestyle modification, pharmacologic therapy, and
revascularization procedures.
Hines RL, Marschall KE. Anesthesia & Co-Existing Diseases.
6th ed. Philadelphia, PA: Elsevier-Saunders; 2012: 4.

Question 27

What are the early treatment aims in a patient who

has had an acute MI?

Answer 27

Evaluate hemodynamic stability, obtain a 12-lead ECG, and
administer oxygen. Morphine and nitroglycerin are typically
administered to relieve chest pain and aspirin is administered to
decrease any further thrombus formation. Re-establishment of
coronary blood flow to reduce the degree of myocardial damage
may be performed via reperfusion therapy or coronary
angioplasty.
Hines RL, Marschall KE. Anesthesia & Co-Existing Diseases.
6th ed. Philadelphia, PA: Elsevier-Saunders; 2012: 4.

Question 28

What types of antiplatelet drugs are used in the

treatment of angina?

Answer 28

Aspirin, adenosine diphosphate inhibitors (clopidogrel and
ticlopidine), and glycoprotein IIb/IIIa antagonists (abciximab and
eptifibatide).
Hines RL, Marschall KE. Anesthesia & Co-Existing Diseases.
6th ed. Philadelphia, PA: Elsevier-Saunders; 2012: 4-6.

Question 29

Why are beta-blockers often prescribed after a

patient has experienced an MI?

Answer 29

Beta-blockers reduce the risk of reinfarction and death by
decreasing myocardial oxygen demand.
Hines RL, Marschall KE. Anesthesia & Co-Existing Diseases.
6th ed. Philadelphia, PA: Elsevier-Saunders; 2012: 6.

Question 30

What drugs are used in reperfusion therapy?

Answer 30

Streptokinase, tissue plasminogen activator, reteplase, or
tenecteplase
Hines RL, Marschall KE. Anesthesia & Co-Existing Diseases.
6th ed. Philadelphia, PA: Elsevier-Saunders; 2012: 9.

Question 31

How long after the onset of symptoms is coronary

angioplasty most effective?

Answer 31

Angioplasty should be performed within 12 hours of the onset of
symptoms. The goal is to perform the procedure within 90
minutes of the patient’s arrival at the hospital.
Hines RL, Marschall KE. Anesthesia & Co-Existing Diseases.
6th ed. Philadelphia, PA: Elsevier-Saunders; 2012: 9.

Question 32

Antiplatelet drugs such as clopidogrel and abciximab
are often given to patients who have experienced a
myocardial infarction. How do these drugs work?

Answer 32

Clopidogrel and ticlopidine inhibit platelet aggregation by
blocking adenosine diphosphate receptors. Abciximab and
eptifibatide inhibit platelet adhesion, activation, and aggregation
by antagonizing platelet glycoprotein IIb/IIIa receptors.
Hines RL, Marschall KE. Anesthesia & Co-Existing Diseases.
6th ed. Philadelphia, PA: Elsevier-Saunders; 2012: 4-5.

Question 33

How does angiotensin II increase the risk for

coronary ischemia?

Answer 33

Excessive angiotensin II levels are associated with myocardial
hypertrophy, myocardial fibrosis, coronary vasoconstriction,
dysfunction of the coronary endothelium, and promotion of
atheroma formation.
Hines RL, Marschall KE. Anesthesia & Co-Existing Diseases.
6th ed. Philadelphia, PA: Elsevier-Saunders; 2012: 6.

Question 34

What is the indication for the use of angiotensinconverting
enzyme inhibitors in patients with
coronary artery disease?

Answer 34

ACE inhibitors are indicated for all patients with CAD, especially
in the presence of co-existing hypertension, diabetes mellitus,
or left ventricular dysfunction.
Hines RL, Marschall KE. Anesthesia & Co-Existing Diseases.
6th ed. Philadelphia, PA: Elsevier-Saunders; 2012: 6.

Question 35

Can beta-blockers be used in patients with
congestive heart failure and pulmonary disease after
an MI?

Answer 35

Although it was once presumed that beta-blockers would exert
deleterious effects in patients with CHF and pulmonary disease,
studies have shown that they are beneficial in reducing the risk
of death even in these patients.
Hines RL, Marschall KE. Anesthesia & Co-Existing Diseases.
6th ed. Philadelphia, PA: Elsevier-Saunders; 2012: 6.

Question 36

What is the most severe complication of thrombolytic

therapy?

Answer 36

Intracranial hemorrhage
Hines RL, Marschall KE. Anesthesia & Co-Existing Diseases.
6th ed. Philadelphia, PA: Elsevier-Saunders; 2012: 9.

Question 37

What patients are most at risk for intracranial

hemorrhage due to thrombolytic therapy?

Answer 37

Patients older than 75 and patients with uncontrolled
hypertension
Hines RL, Marschall KE. Anesthesia & Co-Existing Diseases.
6th ed. Philadelphia, PA: Elsevier-Saunders; 2012: 9.

Question 38

How do long-acting calcium channel blockers
compare to short-acting calcium channel blockers in
their abiliy to relieve anginal pain?

Answer 38

Long-acting calcium channel blockers are as effective as betablockers
at relieving anginal pain. The short-acting agents such
as verapamil and diltiazem, however, do not relieve anginal
pain significantly.
Hines RL, Marschall KE. Anesthesia & Co-Existing Diseases.
6th ed. Philadelphia, PA: Elsevier-Saunders; 2012: 6.

Question 39

How do nitrates improve symptoms of coronary

ischemia?

Answer 39

Nitrates decrease the severity, duration, and frequency of
anginal symptoms by dilating coronary and collateral vessels.
They also produce peripheral vasodilation which decreases
afterload and reduces myocardial oxygen consumption.
Dilation of venous vessels reduces preload and also reduces
myocardial work.
Hines RL, Marschall KE. Anesthesia & Co-Existing Diseases.
6th ed. Philadelphia, PA: Elsevier-Saunders; 2012: 5-6.

Question 40

What are the contraindications to the administration

of nitrates?

Answer 40

They are contraindicated in patients with hypertrophic
obstructive cardiomyopathy and should not be administered to
patients within 24 hours of taking sildenafil, tadalafil, or
vardenafil.
Hines RL, Marschall KE. Anesthesia & Co-Existing Diseases.
6th ed. Philadelphia, PA: Elsevier-Saunders; 2012: 5-6.

Question 41

What is the most common side effect of nitrates?

Answer 41

Headache
Hines RL, Marschall KE. Anesthesia & Co-Existing Diseases.
6th ed. Philadelphia, PA: Elsevier-Saunders; 2012: 6.