Question 1

The shape of the P wave is analyzed to determine whether:

Accepted Answer

C

Question 2

Which sinus rhythm has a rate of less than 60 beats per minute?

Accepted Answer

Sinus bradycardia is characterized by a sinus rhythm with a rate less than 60 beats per minute. Sinus tachycardia is a sinus rhythm with a rate greater than 100 beats per minute. Sinus dysrhythmia is an irregular sinus rhythm with variations in rate with respiration. Normal sinus rhythm is a sinus rhythm with a rate between 60 to 100 beats per minute.

Question 3

The ECG tracing is considered a legal document and needs to be included in the patient's medical record. What four items must be on each ECG tracing?

Accepted Answer

The four items that must be on each ECG tracing are the patient's name, today's date and time, and initials of the ECG technician. The patient's date of birth might be helpful but is not required for legal documentation purposes. Diagnosis and insurance information are also not necessary for the ECG tracing.

Question 4

Which of the following are common symptoms of low cardiac output?

Accepted Answer

Shortness of breath and hypotension are two common symptoms of low cardiac output. Nausea, vomiting, headache, diarrhea, muscle aches, and low back pain are not specific to low cardiac output and may have other causes.

Question 5

Sinus tachycardia may be a normal finding in people as a result of:

Accepted Answer

Sinus tachycardia is a normal finding in people during exercise when the body's demand for oxygen and nutrients increases, leading to an increase in heart rate. It is not a normal finding in people experiencing cardiac arrest, low cardiac output, or hypertension.

Question 6

QRS duration measurement is essential to determine the time it takes for:

Accepted Answer

QRS duration measures the time it takes for ventricular depolarization.

Question 7

What is evaluated and classified when determining dysrhythmias?

Accepted Answer

Waves, segments, and intervals on the ECG tracing are evaluated and classified when determining dysrhythmias, as these elements provide the necessary information about the heart's electrical activity and rhythm.

Question 8

The normal range for the QRS complex duration is:

Accepted Answer

The normal range for the QRS complex duration is 0.06 to 0.10 second, which reflects the time it takes for depolarization (and thus contraction) of both ventricles.

Question 9

Sinus tachycardia is considered serious or life-threatening in patients who have had a recent:

Accepted Answer

Sinus tachycardia can be a normal physiological response to stress, exercise or fever. However, it can also be a sign of significant cardiovascular or metabolic disease, such as myocardial infarction. Therefore, sinus tachycardia should be taken seriously in patients with recent myocardial infarction as it can indicate ongoing ischemia, left ventricular dysfunction, or autonomic dysfunction.

Question 10

The QRS complex represents the time it takes for:

Accepted Answer

The QRS complex represents the depolarization (contraction) of the ventricles, which takes place immediately after the depolarization of the atria (represented by the P wave). Repolarization of the ventricles is represented by the T wave, which comes after the QRS complex. The initiation of the electrical current at the SA node is represented by the P wave, and the current moving through the atria is also represented by the P wave. Therefore, the best choice is A, as it accurately represents the QRS complex.

Question 11

What is the rate of a normal sinus rhythm?

Accepted Answer

A normal sinus rhythm has a rate of 60 to 100 beats per minute (bpm). Choice A is the only option within this range. Choice B is too slow, Choice C is too fast, and Choice D implies a potential arrhythmia.

Question 12

A patient with sinus bradycardia may require what type of treatment?

Accepted Answer

A patient with sinus bradycardia may require medication to increase their heart rate or a pacemaker to regulate their heart rate. Physical therapy, stress tests, IV fluids, oxygen, and open-heart surgery are not typical treatments for sinus bradycardia.

Question 13

The normal PR interval measurement is:

Accepted Answer

The normal PR interval measurement is 0.12 to 0.20 second.

Question 14

Which of the following serves as the pacemaker in a normal heart?

Accepted Answer

The SA (sinoatrial) node is the natural pacemaker of the heart, meaning it initiates the electrical impulses that cause each heartbeat. The AV (atrioventricular) node and Bundle of His help transmit these impulses to the ventricles, but they do not serve as the primary pacemaker. The bundle branches further divide and distribute the impulses to the muscle fibers of the ventricles.

Question 15

Identify the following rhythm:

Accepted Answer

The answer of Identify the following rhythm: 
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Question 16

Which sinus rhythm has a rate of more than 100 beats per minute?

Accepted Answer

Sinus tachycardia is a sinus rhythm with a rate of more than 100 beats per minute, while sinus bradycardia has a rate of less than 60 beats per minute, normal sinus rhythm has a rate of 60-100 beats per minute, and sinus dysrhythmia is a variation in the rate of the normal sinus rhythm.

Question 17

If you can't identify an R wave on the ECG tracing, which of the following wave(s)can you use to determine the regularity of the ventricles?

Accepted Answer

The Q and S wave junction can be used to determine the regularity of the ventricles if the R wave is not identifiable, as it is part of the QRS complex which represents ventricular depolarization.

Question 18

Which of the following questions is necessary to analyze a P wave on an ECG tracing?

Accepted Answer

The presence of a QRS complex following each P wave indicates that each atrial depolarization is followed by ventricular depolarization, which is crucial for assessing the conduction from the atria to the ventricles.

Question 19

Identify a rhythm using these criteria: regular rhythm, ventricular and atrial rates are 74 beats/minute, P wave precedes each QRS, PR interval and QRS duration within normal limits.

Accepted Answer

The given criteria describe a normal sinus rhythm where the ventricular and atrial rates are 74 beats/minute, P wave precedes each QRS, PR interval and QRS duration are within normal limits, and the rhythm is regular. Thus, option C is the best choice.

Question 20

Measuring the PR interval requires the ECG technician to measure from the:

Accepted Answer

The PR interval is measured from the beginning of the P wave to the beginning of the QRS complex, as it represents the time for the electrical impulse to travel from the sinoatrial node through the atria and through the atrioventricular node before reaching the ventricles.

Quiz 5: Rhythm Strip Interpretation and Sinus Rhythms