Cardiac Ischemia and Infarction: EKG Interpretation for Medical Assistants

Question 1

An ST-segment elevation of 2mm or more in two contiguous leads suggests:

Accepted Answer

Myocardialinfarction

Answer

Myocardialischemia

Answer

Pericarditis

Answer

Ventriculartachycardia

Question 2

A reciprocal ST-segment depression in leads opposite to those showing ST elevation:

Accepted Answer

Indicates a more extensive area of ischemia

Answer

Rules out the possibility of myocardial infarction

Answer

Is a normal finding in healthy individuals

Answer

May indicate a false-positive EKG result

Question 3

Differentiate between STEMI and NSTEMI:

Accepted Answer

STEMI involves complete blockage, NSTEMI involves partial blockage

Answer

STEMI involves partial blockage, NSTEMI involves complete blockage

Answer

They are the same

Answer

NSTEMI is more serious than STEMI

Question 4

What is the significance of a Q wave in EKG interpretation?

Accepted Answer

Indicates a previous myocardial infarction

Answer

Predicts a high risk of ventricular arrhythmias

Answer

Suggests a conduction defect

Answer

Is not clinically significant

Question 5

A patient presents with chest pain. Their EKG shows ST-segment depression in leads V4-V6. What is the most likely underlying pathology?

Accepted Answer

Myocardial ischemia

Answer

Myocardial infarction

Answer

Pericarditis

Answer

Left ventricular hypertrophy

Question 6

To evaluate anteroseptal myocardial ischemia, which lead placement is commonly used?

Accepted Answer

Lead V1

Answer

Lead I

Answer

Lead V4

Answer

Lead aVR

Question 7

Differentiate between ST-segment elevation and ST-segment depression.

Accepted Answer

Depression suggests ischemia, while elevation indicates infarction

Answer

Elevation suggests ischemia, while depression indicates infarction

Answer

Both reflect ischemia, but in different myocardial layers

Answer

There is no distinction between the two

Question 8

Which patient presentation is often associated with a non-ST-elevation myocardial infarction?

Accepted Answer

Prolonged chest discomfort with nausea and sweating

Answer

Sudden onset of severe chest pain radiating to the back

Answer

Unstable angina progressing to complete heart block

Answer

Asymptomatic presentation with elevated cardiac enzymes

Question 9

Which EKG change is the most definitive indicator of an acute myocardial infarction?

Accepted Answer

ST-segment elevation

Answer

ST-segment depression

Answer

T-wave inversion

Answer

Q-wave

Question 10

What do reciprocal ST-segment changes on an EKG suggest?

Accepted Answer

An ischemic area located opposite the ST-segment changes.

Answer

A normal variant that requires no further evaluation.

Answer

Chronic heart failure.

Answer

Always associated with ST-segment elevation.

Question 11

Which EKG finding is a late manifestation of myocardial infarction?

Accepted Answer

Pathologic Q-wave

Answer

ST-segment elevation

Answer

T-wave inversion

Answer

Prolonged PR interval

Question 12

Which medication is commonly used to treat myocardial ischemia?

Accepted Answer

Nitroglycerin

Answer

Aspirin

Answer

Heparin

Answer

Morphine

Question 13

What is the primary purpose of a stress test in evaluating cardiac ischemia?

Accepted Answer

To induce ischemia and assess myocardial blood flow.

Answer

To rule out other causes of chest pain.

Answer

To determine the extent of coronary artery disease.

Answer

To predict the risk of future cardiac events.

Question 14

In EKG interpretation, what does the presence of a Q wave typically suggest?

Accepted Answer

Myocardial scarring or infarction

Answer

Normal heart function

Answer

Electrical instability in the heart

Question 15

In a 12-lead EKG, which lead provides the clearest view of the posterior wall of the heart?

Accepted Answer

Lead V6

Answer

Lead I

Answer

Lead II

Answer

Lead V1

Question 16

True or False: Myocardial infarction occurs when there is a partial blockage of blood flow to a portion of the heart muscle.

Accepted Answer

False

Answer

True

Question 17

What is the primary purpose of administering oxygen to a patient experiencing myocardial ischemia?

Accepted Answer

Increase oxygen supply to the heart muscle

Answer

Reduce inflammation

Answer

Dilate blood vessels

Answer

Lower blood pressure

Question 18

What is the key difference between transmural and non-transmural myocardial infarctions?

Accepted Answer

Transmural infarctions affect the entire thickness of the heart muscle, while non-transmural infarctions do not.

Answer

Non-transmural infarctions are more common than transmural infarctions.

Answer

Non-transmural infarctions are more likely to cause heart failure than transmural infarctions.

Answer

Transmural infarctions have a lower mortality rate than non-transmural infarctions.

Question 19

Which of the following ECG patterns is associated with anterior myocardial infarction?

Accepted Answer

Q waves in leads V1-V4

Answer

ST segment depression in leads II, III, and aVF

Answer

T wave inversion in leads III and aVF

Answer

PR interval prolongation

Question 20

What is the key difference between ST segment depression and ST segment elevation?

Accepted Answer

Direction of the change

Answer

Depth of the change

Answer

Duration of the change

Answer

Underlying etiology

Question 21

Which of the following EKG changes is indicative of myocardial ischemia?

Accepted Answer

ST segment depression

Answer

ST segment elevation

Answer

T wave inversion

Answer

Q wave

Question 22

Which of the following EKG patterns is associated with bundle branch block?

Accepted Answer

Wide QRS complex

Answer

Narrow QRS complex

Answer

Inverted T waves

Answer

ST segment elevation

Question 23

Which EKG change is a characteristic finding of acute myocardial ischemia?

Accepted Answer

ST-segment elevation of ≥ 0.2 mV in ≥ 2 contiguous leads

Answer

ST-segment depression of ≥ 0.1 mV in ≥ 2 contiguous leads

Answer

T-wave inversion of ≥ 0.2 mV in ≥ 2 contiguous leads

Answer

P-wave prolongation of ≥ 0.12 seconds

Question 24

Which of the following is the most common EKG abnormality associated with myocardial infarction?

Accepted Answer

ST-segment elevation

Answer

Prolonged PR interval

Answer

Ventricular tachycardia

Answer

Atrial fibrillation

Question 25

Which EKG lead provides the optimal view of the inferior wall of the heart?

Accepted Answer

Lead III

Answer

Lead II

Answer

Lead V1

Answer

Lead aVL

Question 26

What is the significance of a Q wave that exceeds 0.04 seconds in duration?

Accepted Answer

Indicates myocardial infarction

Answer

Suggests left ventricular hypertrophy

Answer

Is a normal finding in young athletes

Answer

Requires further evaluation with additional testing

Question 27

Which of the following EKG findings is characteristic of pericarditis?

Accepted Answer

PR segment depression

Answer

ST-segment elevation

Answer

T-wave inversion

Answer

Ventricular arrhythmias

Question 28

What is the primary reason for monitoring the QT interval?

Accepted Answer

To assess the risk of ventricular arrhythmias

Answer

To diagnose electrolyte imbalances

Answer

To determine the heart rate

Answer

To evaluate cardiac conduction

Question 29

Which of the following medications can prolong the QT interval and increase the risk of torsades de pointes?

Accepted Answer

Digoxin

Answer

Metformin

Answer

Ibuprofen

Answer

Acetaminophen

Question 30

Which cardiac arrhythmia is the leading cause of sudden cardiac death?

Accepted Answer

Ventricular fibrillation

Answer

Asystole

Answer

Pulseless electrical activity

Answer

Bradycardia

Question 31

Identify the EKG pattern characteristic of **acute ST-elevation myocardial infarction (STEMI)**.

Accepted Answer

ST-segment elevation ≥2 mm in ≥2 contiguous leads

Answer

ST-segment depression ≥1 mm in ≥2 contiguous leads

Answer

T-wave inversion in ≥3 contiguous leads

Answer

QRS complex widening >120 milliseconds

Question 32

Which of the following is **NOT** a recognized risk factor for developing myocardial ischemia?

Accepted Answer

Regular exercise

Answer

Smoking

Answer

High blood pressure

Answer

Diabetes

Question 33

Which of the following medications is **NOT** commonly used in the treatment of **unstable angina**?

Accepted Answer

Morphine

Answer

Aspirin

Answer

Nitroglycerin

Answer

Beta-blockers

Question 34

Which of the following EKG findings is the earliest indicator of myocardial ischemia?

Accepted Answer

ST segment depression

Answer

Prolonged QT interval

Answer

Inverted T waves

Answer

ST segment elevation

Question 35

A patient presents with chest pain and an EKG showing ST segment elevation in leads II, III, and aVF. What is the most likely diagnosis?

Accepted Answer

Inferior ST-segment elevation myocardial infarction (STEMI)

Answer

Myocardial ischemia

Answer

Anterior ST-segment elevation myocardial infarction (STEMI)

Question 36

Which of the following is a modifiable risk factor for cardiac infarction?

Accepted Answer

Smoking

Answer

Gender

Answer

Age

Answer

Family history

Question 37

What is the most common symptom of cardiac infarction?

Accepted Answer

Chest pain or discomfort

Answer

Shortness of breath

Answer

Nausea

Answer

Fatigue

Question 38

Which enzyme is a specific marker for cardiac infarction and is elevated in the blood within 3-12 hours after the onset of symptoms?

Accepted Answer

Creatine kinase-MB (CK-MB)

Answer

Aspartate aminotransferase (AST)

Answer

Alanine aminotransferase (ALT)

Answer

Lactate dehydrogenase (LDH)

Question 39

What is the primary goal of reperfusion therapy in cardiac infarction?

Accepted Answer

To restore blood flow to the ischemic myocardium and limit infarct size

Answer

To dissolve blood clots

Answer

To reduce inflammation

Answer

To prevent arrhythmias

Question 40

Which of the following lifestyle modifications is most effective in preventing cardiac infarction?

Accepted Answer

Regular exercise

Answer

Ketogenic diet

Answer

Intermittent fasting

Question 41

Which of the following EKG patterns is indicative of a right bundle branch block?

Accepted Answer

Wide QRS complex with a terminal R wave in lead V1

Answer

Normal QRS complex with a tall R wave in lead V5

Answer

Wide QRS complex with a terminal S wave in lead V1

Answer

Narrow QRS complex with an inverted T wave in lead III