Cardiology I Review

Question 1

Atrial fibrillation can be interpreted by noting:
Select one:
a. PR intervals that vary from complex to complex.
b. an irregularly irregular rhythm and absent P waves.
c. a regularly irregular rhythm with abnormal P waves.
d. the presence of wide QRS complexes and a rapid rate.

Answer 1

b. an irregularly irregular rhythm and absent P waves.

Question 2

Supraventricular tachycardia is MOST accurately defined as:
Select one:
a. any tachycardic rhythm with a heart rate greater than 130 beats/min and absent P waves.
b. a tachycardic rhythm originating from a pacemaker site above the level of the ventricles.
c. an irregular tachycardic rhythm that originates just below the AV junction.
d. a regular tachycardic rhythm between 150 and 180 beats/min with P waves buried in the QRS complexes.

Answer 2

b. a tachycardic rhythm originating from a pacemaker site above the level of the ventricles.

Question 3

Electrical capture during transcutaneous cardiac pacing is characterized by:
Select one:
a. the presence of a strong pulse, despite a slow rate.
b. a pacemaker spike followed by a wide QRS complex.
c. narrow QRS complexes that are preceded by a pacemaker spike.
d. low-amplitude QRS complexes preceded by a pacemaker spike.

Answer 3

b. a pacemaker spike followed by a wide QRS complex.

Question 4

A patient with right ventricular failure would most likely present with:
Select one:
a. an enlarged liver.
b. collapsed jugular veins.
c. rhonchi in the lungs.
d. pulmonary edema.

Answer 4

a. an enlarged liver.

Question 5

Premature ventricular complexes (PVCs) that originate from different sites in the ventricle:
Select one:
a. are called unifocal PVCs. 
b. produce a palpable pulse.
c. are also called fusion PVCs.
d. will appear differently on the ECG.

Answer 5

d. will appear differently on the ECG.

Question 6

A major complication associated with atrial fibrillation is:
Select one:
a. clot formation in the fibrillating atria.
b. a significant reduction in atrial filling.
c. pulmonary congestion and hypoxemia.
d. a profound increase in the atrial kick.

Answer 6

a. clot formation in the fibrillating atria.

Question 7

The 6-second method for calculating the rate of a cardiac rhythm:
Select one:
a. involves counting the number of QRS complexes in a 6-second strip and multiplying that number by 10.
b. is an accurate method for calculating the heart rate if the cardiac rhythm is grossly irregular and very fast.
c. will yield an estimated heart rate that is typically within 2 to 3 beats per minute of the actual heart rate.
d. takes longer than other methods of calculating the rate and is thus impractical to use with critical patients.

Answer 7

a. involves counting the number of QRS complexes in a 6-second strip and multiplying that number by 10.

Question 8

The left main coronary artery subdivides into the:
Select one:
a. left anterior ascending and descending arteries.
b. left anterior descending and circumflex arteries.
c. left posterior ascending and circumflex arteries.
d. right coronary and left posterior descending arteries.

Answer 8

b. left anterior descending and circumflex arteries.

Question 9

In sinus bradycardia, the:
Select one:
a. heart rate is less than 70 beats/min.
b. pacemaker site is the SA node. 
c. QRS complexes are often wide.
d. P waves are consistently upright.

Answer 9

b. pacemaker site is the SA node.

Question 10

An electrical wave moving in the direction of a positive electrode will:
Select one:
a. cause a positive deflection on the ECG.
b. produce a significant amount of artifact.
c. cause a negative deflection on the ECG.
d. manifest with narrow QRS complexes.

Answer 10

a. cause a positive deflection on the ECG.

Question 11

A “runaway” pacemaker is characterized by:
Select one:
a. an absence of pacemaker spikes. 
b. profound slowing of the heart rate.
c. a tachycardic pacemaker rhythm.
d. a narrowing of the QRS complexes.

Answer 11

c. a tachycardic pacemaker rhythm.

Question 12

A first-degree heart block has a PR interval greater than 0.20 seconds because:
Select one:
a. depolarization of the atria occurs at a slightly slower rate than one would expect.
b. each impulse that reaches the AV node is delayed slightly longer than expected.
c. impulses generated by the SA node traverse the AV node at an accelerated rate.
d. the primary pacemaker is not the SA node, but rather an ectopic atrial pacemaker.

Answer 12

b. each impulse that reaches the AV node is delayed slightly longer than expected.

Question 13

An early complex that breaks the regularity of the underlying rhythm and that is characterized by a narrow QRS complex and an upright P wave that differs in shape and size from the P waves of the other complexes MOST accurately describes aNo:
Select one:
a. atrial escape complex.
b. wandering atrial pacemaker.
c. junctional escape complex.
d. premature atrial complex.

Answer 13

d. premature atrial complex.

Question 14

Patients with a continuous-flow ventricular assist device:
Select one:
a. cannot receive epinephrine if they are bradycardic.
b. may not have a palpable pulse, despite adequate perfusion.
c. have a BP that is 20 to 30 mm Hg higher than it actually is.
d. should be defibrillated with a higher-than-normal energy setting.

Answer 14

b. may not have a palpable pulse, despite adequate perfusion.

Question 15

The duration of the QRS complex should be \_\_\_\_ milliseconds or less in a healthy adult.
Select one:
a. 100 
b. 110
c. 120
d. 130

Answer 15

b. 110

Question 16

The AV junction:
Select one:
a. includes the AV node but not the bundle of His.
b. is the dominant and fastest pacemaker in the heart.
c. receives its blood supply from the circumflex artery.
d. is composed of the AV node and surrounding tissue.

Answer 16

d. is composed of the AV node and surrounding tissue.

Question 17

A key to interpreting a Mobitz type II second-degree heart block is to remember that:
Select one:
a. unlike a Mobitz type I second-degree heart block, a type II heart block is always regular.
b. in this type of heart block, the PR interval gets progressively longer until a P wave is not conducted.
c. the PR interval of all of the conducted P waves and their corresponding QRS complexes is constant.
d. most type II second degree AV blocks have more than two nonconducted P waves that occur in succession.

Answer 17

c. the PR interval of all of the conducted P waves and their corresponding QRS complexes is constant.

Question 18

A demand pacemaker:
Select one:
a. generates pacing impulses only when it senses that the heart’s natural pacemaker has fallen below a preset rate.
b. sends out single electrical impulses when the patient’s inherent pacemaker rate exceeds 150 beats/min.
c. is easily identified on a cardiac rhythm strip by noting the presence of pacer spikes before all of the QRS complexes.
d. attaches to the atria and the ventricles and only generates an impulse if it senses that the patient is in ventricular fibrillation.

Answer 18

a. generates pacing impulses only when it senses that the heart’s natural pacemaker has fallen below a preset rate.

Question 19

On the ECG graph paper, 6 seconds is represented by how many large boxes?
Select one:
a. 20 
b. 30
c. 40
d. 50

Answer 19

b. 30

Question 20

What layer of the heart is responsible for cardiac contraction and efficient ejection of blood?
Select one:
a. Myocardium 
b. Endocardium
c. Epicardium
d. Pericardium

Answer 20

a. myocardium

Question 21

The treatment for sinus tachycardia should focus on:
Select one:
a. decreasing the heart rate.
b. correcting the underlying cause. 
c. administering IV fluid boluses.
d. relieving pain and anxiety.

Answer 21

b. correcting the underlying cause.

Question 22

When applying the limb leads, the negative lead should be placed on the:
Select one:
a. left arm. 
b. left leg.
c. right arm.
d. right leg.

Answer 22

c. right arm.

Question 23

A decreased cardiac output secondary to a heart rate greater than 150 beats/min is caused by:
Select one:
a. myocardial stretching due to increased preload.
b. decreases in stroke volume and ventricular filling.
c. increased automaticity of the cardiac pacemaker.
d. ectopic pacemaker sites in the atria or ventricles.

Answer 23

b. decreases in stroke volume and ventricular filling.

Question 24

According to the Einthoven triangle, lead II is assessed by placing the:
Select one:
a. negative lead on the left arm and the positive lead on the left leg.
b. positive lead on the left leg and the negative lead on the right arm.
c. positive lead on the left arm and the negative lead on the right arm.
d. negative lead on the right arm and the positive lead on the left leg.

Answer 24

d. negative lead on the right arm and the positive lead on the left leg.

Question 25

. The \_\_\_\_\_\_\_\_\_\_ represents the end of ventricular depolarization and the beginning of repolarization.
Select one:
a. J point
b. T wave 
c. ST segment
d. T-P interval

Answer 25

a. J point

Question 26

The right atrium, right ventricle, and part of the left ventricle are supplied by the:
Select one:
a. circumflex artery.
b. left anterior descending artery.
c. left main coronary artery.
d. right coronary artery.

Answer 26

d. right coronary artery.

Question 27

A “run” of ventricular tachycardia occurs if at least \_\_\_\_ PVCs occur in a row.
Select one:
a. two
b. three 
c. four
d. five

Answer 27

b. three

Question 28

A regular cardiac rhythm with a rate of 104 beats/min, upright P waves, a PR interval of 0.14 seconds, and QRS complexes that measure 0.10 seconds should be interpreted as:
Select one:
a. supraventricular tachycardia.
b. normal sinus rhythm. 
c. sinus tachycardia.
d. junctional tachycardia.

Answer 28

c. sinus tachycardia.

Question 29

A classic sign of atrial flutter is:
Select one:
a. a constant 2:1 conduction ratio.
b. the presence of sawtooth F waves.
c. a ventricular rate less than 100 beats/min.
d. an irregular but consistent R-R interval.

Answer 29

b. the presence of sawtooth F waves.

Question 30

The PR interval should be no shorter than \_\_\_\_ seconds and no longer than \_\_\_\_ seconds in duration.
Select one:
a. 0.12, 0.20 
b. 0.14, 0.30
c. 0.16, 0.40
d. 0.18, 2.0

Answer 30

a. 0.12, 0.20

Question 31

The firing of an artificial ventricular pacemaker causes:
Select one:
a. a change in the shape of the preceding P waves.
b. a vertical spike followed by a wide QRS complex.
c. a small spike followed by a narrow QRS complex.
d. a wide QRS complex followed by a vertical spike.

Answer 31

b. a vertical spike followed by a wide QRS complex.

Question 32

An unresponsive, pulseless, apneic patient presents with ventricular tachycardia on the cardiac monitor. After defibrillating the patient, you should:
Select one:
a. take no more than 10 seconds to assess for a pulse.
b. resume CPR and reassess the patient after 2 minutes.
c. reassess the cardiac rhythm to see if it has changed.
d. deliver another shock if his cardiac rhythm is unchanged.

Answer 32

b. resume CPR and reassess the patient after 2 minutes.

Question 33

A second-degree heart block, Mobitz type I, occurs when:
Select one:
a. every other impulse generated by the SA node is blocked at the AV node and does not depolarize the ventricles.
b. each successive impulse is progressively delayed, until one impulse is blocked from entering the ventricles.
c. the PR interval progressively grows narrower, until there is a P wave that is not followed by a QRS complex.
d. more than one successive impulse from the SA node is blocked at the AV node and is not allowed to enter the ventricles.

Answer 33

b. each successive impulse is progressively delayed, until one impulse is blocked from entering the ventricles.

Question 34

You and your partner arrive at the scene of an unresponsive male patient. Your assessment reveals that he is pulseless and apneic. The patient’s wife tells you that he collapsed about 10 minutes ago. You should:
Select one:
a. ask the patient’s wife if her husband has a living will.
b. apply the defibrillator pads and assess his cardiac rhythm.
c. initiate CPR as your partner applies the defibrillator pads.
d. begin CPR with a compression to ventilation ratio of 15:2.

Answer 34

c. initiate CPR as your partner applies the defibrillator pads.

Question 35

After delivering a shock to a patient in pulseless ventricular tachycardia, you should:
Select one:
a. resume CPR. 
b. check for a pulse.
c. reassess the cardiac rhythm.
d. deliver two effective ventilations.

Answer 35

a. resume CPR.