NHA CET Exam Questions

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61.

What is the defining characteristic of a premature ventricular contraction (PVC)?

  • Wide, irregular QRS complex

  • Chaotic atrial activity

  • Occurrence of P waves at a rate of 250-350 beats per minute

  • It requires immediate cardiopulmonary resuscitation

Correct answer: Wide, irregular QRS complex

A premature ventricular contraction will be displayed as a rhythm containing wide, irregular QRS complexes.

Chaotic atrial activity or irregular, frequent P waves is/are a sign of atrial fibrillation. The occurrence of P waves at over 250 per minute is seen in atrial flutter. Ventricular fibrillation is a lethal rhythm, as the ventricle is quivering and the heart is not actively pumping; this rhythm requires cardiopulmonary resuscitation.

62.

An EKG technician is preparing a patient for continuous telemetry monitoring. 

Which of the following actions should the technician perform to ensure accurate electrode placement and signal quality?

  • Shave excessive chest hair and clean the skin with alcohol before applying the electrodes

  • Apply extra adhesive tape over the electrodes to prevent them from detaching due to excessive sweating

  • Position the right arm (RA) electrode just below the right clavicle and the left leg (LL) electrode below the right rib cage

  • Place the electrodes on bony areas, such as the clavicle, to minimize movement artifact

Correct answer: Shave excessive chest hair and clean the skin with alcohol before applying the electrodes

This helps remove oils and debris from the skin surface, reducing impedance and improving electrode contact. Proper skin preparation minimizes the risk of artifacts, ensuring more accurate EKG recordings.

Placing electrodes on bony areas can result in poor signal quality and increased motion artifacts. Electrodes should be placed on soft tissue areas to ensure better contact and less movement interference.

In telemetry, the right arm (RA) electrode should be placed just below the right clavicle and the left leg (LL) electrode should be placed below the left rib cage or lower abdomen for a 5-lead configuration. For a 3-lead configuration, the electrodes should be placed on the right arm, left arm, and left leg positions.

While extra adhesive tape may secure the electrodes, it does not address the underlying issue of poor electrode contact due to skin oils, hair, or dirt. Proper skin preparation is more effective in ensuring stable contact and signal quality.

63.

While analyzing an EKG tracing, you notice an early beat with an abnormally shaped P wave followed by a narrow QRS complex. 

Which of the following best describes this finding and its likely cause?

  • Premature atrial complex (PAC); caused by an irritable focus in the atria

  • Ventricular tachycardia; caused by an irritable focus in the ventricles

  • Atrial fibrillation; caused by rapid, irregular atrial activity

  • First-degree heart block; caused by a delay in conduction through the AV node

Correct answer: Premature atrial complex (PAC); caused by an irritable focus in the atria

A premature atrial complex (PAC) occurs when an ectopic focus within the atria fires earlier than the normal sinus beat, resulting in an early, abnormally shaped P wave followed by a narrow QRS complex. PACs are typically benign but can sometimes indicate atrial irritability or increased atrial excitability. The narrow QRS complex suggests that the impulse is conducted normally through the ventricles. 

Ventricular tachycardia presents with wide QRS complexes (not narrow) and is initiated by irritable foci in the ventricles (not the atria). 

Atrial fibrillation is characterized by an irregular, chaotic baseline without distinct P waves. 

First-degree heart block involves a prolonged PR interval, not early atrial activity.

64.

A patient arrives at the ER. His family member reports that he passed out at a grocery store and was transported for further evaluation. A quick assessment of his vital signs reveals that he is breathing adequately and has a strong pulse
with a heart rate of 58 beats per minute. He is alert and oriented. 

These signs could point to which condition?

  • Stokes-Adams syncope

  • Cardiogenic shock

  • Ventricular tachycardia

  • Cyanotic heart disease

Correct answer: Stokes-Adams syncope

Stokes-Adams syncope is a condition in which a patient suddenly faints from inadequate cardiac output. Bradycardia, strong pulse, and normal respirations without a change in mental status point to this type of syncopal episode. 

Cardiogenic shock, ventricular tachycardia, and cyanotic heart disease are often associated with tachycardia (increased heart rate), weak pulse, and abnormal respirations.

65.

What is the defining characteristic of ventricular fibrillation?

  • Lack of QRS complexes

  • Lack of electrical activity

  • Rate of between 120 and 200 beats per minute

  • Three or more consecutive PVCs

Correct answer: Lack of QRS complexes

The hallmark of ventricular fibrillation is the lack of QRS complexes; rather than beating, the ventricular walls are quivering instead of pumping.

Because there is no cardiac output occurring, tachycardia does not appear during ventricular fibrillation. Three or more consecutive PVCs are typically seen in ventricular tachycardia. Asystole is the total lack of electrical activity and is illustrated by a line with no waves.

66.

What does hypertrophy mean?

  • An increase in muscle mass

  • An increase in contractility

  • An increase in polarization

  • A decrease in repolarization

Correct answer: An increase in muscle mass

Hypertrophy refers to an increase in muscle mass. This physiological process occurs when muscle fibers enlarge due to increased demand or stress, such as from resistance training or other forms of exercise. The increase in muscle size results from the growth of individual muscle cells, enhancing the muscle's overall strength and functionality.

Contractility refers to the heart muscle's ability to contract.

Polarization is the process of creating an electrical charge difference across a cell membrane.

Repolarization is the return of the cell membrane's electrical state to its resting potential after depolarization.

67.

What does "aV" represent?

  • Augmented voltage

  • Axial voltage

  • Axillary voltage

  • Arm voltage

Correct answer: Augmented voltage

The letters aV stand for augmented voltage: the current emitting from the augmented leads. The letters that follow (R, L, F) stand for the position of the lead.

68.

Which of the following is true about non-Q-wave myocardial infarctions?

  • They are associated with T-wave inversion and ST-segment depression

  • Q waves must be present to diagnose a myocardial infarction

  • They produce ST-segment elevation

  • Non-Q-wave myocardial infarctions are associated with a very low mortality rate

Correct answer: They are associated with T-wave inversion and ST-segment depression

Non-ST-segment elevation myocardial infarctions, or "non-STEMIs," do not lead to the evolution of deep Q waves. The only EKG changes you will see are T-wave inversion and ST-segment depression (not elevation) with these types of myocardial infarctions. 

Cardiologists take these signs very seriously because these patients have a high risk of future infarctions and death.

69.

Stress testing is what kind of method for assessing the presence and severity of coronary artery disease?

  • Noninvasive

  • Invasive

  • Idiopathic

  • Dangerous

Correct answer: Noninvasive method

Stress testing is a noninvasive method for assessing the presence or severity of coronary artery disease. Noninvasive does not require instruments entering the body, whereas invasive would. Idiopathic is a general term meaning an unknown cause.

70.

Diastole can be broken into three phases. During which phase do the atria contract, squeezing the remainder of the blood into the ventricles?

  • Atrial kick

  • Diastasis

  • Rapid filling phase

  • Isovolumetric contraction

Correct answer: Atrial kick

The phases of diastole are as follows:

  1. Rapid filling phase - The AV valves are open, and blood flows into the ventricles.
  2. Diastasis - The pressure between the atria and ventricles begins to equalize.
  3. Atrial kick - The atria contract and expel what little blood is in the chambers into the ventricles.

Isovolumetric relaxation is a phase of systole.

71.

What occurs when one of the lower pacemakers begins to fire at an accelerated rate and steals control from the predominant pacemaker?

  • Usurpation

  • Escape

  • Junctional rhythm

  • Bradycardia

Correct answer: Usurpation

Usurpation occurs when the cells of a lower pacemaker become irritable and take over the electrical impulse from the higher pacemaker. This results in a higher heart rate.

Escape is when the lower pacemaker takes control of the electrical impulse after the higher pacemaker fails. Bradycardia is a rate below 60 beats per minute. A junctional rhythm is when electrical impulses begin specifically at the AV node, resulting in a narrow QRS complex.

72.

Which of the following statements is true regarding microshocks?

  • The shock is caused by a damaged or frayed cord

  • It is a dangerous shock sent directly to the heart via defibrillator pads

  • It is a low-voltage shock that does not affect the patient

  • It occurs when a current produced around the pacemaker is harmlessly carried to the power outlet by an insulated cord

Correct answer: The shock is caused by a damaged or frayed cord 

A microshock is dangerous because the current is delivered directly to the patient’s heart. If the grounding wire is exposed, a small current can travel to the pacemaker and shock the heart from the inside. This is more dangerous than a macroshock due to the wet environment of the body. Always check wires for damage before using an EKG machine.

73.

Determine the heart rate of the following EKG rhythm.

  • 100

  • 150

  • 110

  • 90

Correct answer: 100

This is a regular rhythm interrupted by a premature beat. For these types of rhythms, use the little block or memory method and do not count the premature beat. The heart rate in this strip is 100.

74.

Which of the following heart rhythms is treated with atropine?

  • Bradycardia

  • Tachycardia

  • Sinus arrhythmia

  • Supraventricular tachycardia

Correct answer: Bradycardia 

Atropine, when given, increases a patient’s heart rate. Therefore, it should be avoided at all costs if a patient is already tachycardic. It is used for symptoms such as bradycardia and persistent sinus arrests and sinus block.

75.

Identify the rhythm.

  • Wandering atrial pacemaker

  • Atrial pacing

  • Ventricular pacing

  • Multifocal atrial tachycardia

Correct answer: Wandering atrial pacemaker

The rhythm is being depolarized by a ventricular pacemaker, as evidenced by the spike before the wide QRS complex. Wandering atrial pacemaker is not a rhythm in which an external pacemaker is used, so pacer spikes would not be evident. In wandering atrial pacemaker, the natural pacemaker of the heart's rhythm is not the SA node as normal, but pacemaking activity originates from different locations within the atria.

In atrial pacing, a spike precedes a P wave. Both of these spikes occur in dual-chamber pacing. Cardioversion is used when a patient is in acute atrial flutter/atrial fibrillation.

76.

What is the defining sign that a patient has a cardiac pacemaker?

  • A vertical spike

  • A premature ventricular contraction

  • A third-degree AV block

  • A wide, bizarre QRS complex

Correct answer: A vertical spike

The presence of a cardiac pacemaker is determined by the presence of a vertical spike preceding the P wave (atrial pacemaker), preceding the QRS complex (ventricular pacemaker), or both (dual-chamber pacemaker).

A premature ventricular contraction is an extra heartbeat that originates in the ventricles and occurs earlier than the next expected regular heartbeat. It is not related to the presence of a pacemaker.

A third-degree AV block is a condition where there is a complete disconnection between the atria and ventricles, resulting in independent atrial and ventricular rhythms. While a pacemaker may be used to treat this condition, the block itself is not a sign of a pacemaker.

A wide, bizarre QRS complex may indicate ventricular arrhythmias or conduction abnormalities but is not a definitive sign of a pacemaker.

77.

All of the following are normal findings for an infant patient except:

  • A heart rate below 100

  • A short PR interval

  • A shortened QRS complex

  • A heart rate of 150

Correct answer: A heart rate below 100

An infant's normal heart rate is between 100 and 150 due to the heart's small size and their body's metabolic needs. Because of this, the PR intervals and QRS complex will be shorter. A heart rate below 100 is an abnormal finding.

78.

Which of the following is true regarding idioventricular rhythms?

  • There are no P waves

  • It is an irregular rhythm

  • The rate is usually between 40 and 100

  • It is not a lethal rhythm

Correct answer: There are no P waves 

An idioventricular rhythm originates in the ventricles when the higher pacemakers have failed to generate an impulse. It is a regular rhythm, and the rate is between 20 and 40. It has no P waves and wide, bizarre QRS complexes. It is caused by prolonged hypoxia resulting in cardiac damage and is a lethal rhythm that needs cardiopulmonary resuscitation.

79.

Which of the following is the group of pacemaker cells responsible for firing an action potential?

  • Sinoatrial (SA) node

  • Atrioventricular (AV) node

  • Myosin

  • Purkinje fibers

Correct answer: Sinoatrial (SA) node 

The SA node is a group of cells located in the right atrium. These cells are responsible for generating electrical impulses that pass through the heart and stimulate contraction. For this reason, the SA node is known as the natural pacemaker of the heart. 

The electrical signal is sent to the AV node, which is responsible for regulating the impulses sent to the ventricles. Purkinje fibers then send the signal to the ventricles, stimulating contraction. Myosin is a protein that supports the physical act of muscle contraction.

80.

Which of the following is the most accurate way to calculate a normal heart rate?

  • The 1500 method

  • The 300 method

  • The cardiac ruler method

  • The 10-second method

Correct answer: The 1500 method

The 1500 method is a precise way to calculate heart rate, especially for regular rhythms. To use this method, count the number of small boxes between two R waves and divide 1500 by that number. The result is the heart rate in beats per minute (bpm).

The cardiac ruler method, also called the sequence method, is another common method but is less precise than the 1500 method because it rounds the heart rate to the nearest commonly used value. It calculates heart rate by counting the number of large boxes between R waves using a number sequence (e.g., 300, 150, 100, etc.). This method is only used for regular rhythms.

The 300 method involves dividing 300 by the number of large boxes between R waves to estimate the heart rate. It is quick but less precise for irregular rhythms.

The 10-second method is often used for irregular rhythms. It involves counting the number of R waves in a 10-second strip and multiplying by 6 to estimate the heart rate, but it is less accurate than the other methods for regular rhythms.