Chapter 28: Disorders of Cardiac Conduction and Rhythm

The nurse is caring for a client who develops atrial fibrillation. What concern is the highest priority for this client? -An irregular atrial rhythm -An elevated atrial rhythm -The risk of emboli -The impact on ventricular rate

-The risk of emboli

A nurse is caring for a client with an average heart rate of 56 beats/min. The client has no adverse symptoms associated with this heart rate and is receiving no treatment. Which activity modification should the nurse suggest to avoid further slowing of the heart rate? -"Avoid stress or overexcitement." -"Avoid bearing down while having a bowel movement." -"Avoid strenuous aerobic exercise." -"Limit your intake of caffeinated drinks."

-"Avoid bearing down while having a bowel movement."

Considering the PQRST complex of an electrocardiogram (ECG), which letter designation represents atrial depolarization? -P wave -T wave -QRS complex -ST segment

-P wave

A client with a history of angina presents with uncharacteristic chest pain. The subsequent electrocardiogram (ECG) reveals T-wave elevation. This finding suggests an abnormality with which aspects of the cardiac cycle? -Atrial depolarization -Ventricular depolarization -Ventricular repolarization -Depolarization of the atrioventricular node, bundle branches, and Purkinje system

-Ventricular repolarization

Which client will the nurse prioritize to assess first? -client with respiratory sinus arrhythmia -client with sinus bradycardia -client with sinus arrest -client with tachycardia

-client with sinus arrest

When explaining a new diagnosis of complete heart block to a client and family, the nurse should include which statement? -"This means that your atria are not contracting normally; they are quivering." -"One consequence of this type of block is a very slow heart rate that limits circulation to the brain." -"This type of dysrhythmia requires defibrillation, which will occur in the cardiac catheter lab later today." -"It's pretty common for everyone to experience this dysrhythmia, especially during times of stress in their lives."

-"One consequence of this type of block is a very slow heart rate that limits circulation to the brain."

A 20-year-old college student, with no past medical history, arrives at the emergency room complaining of severe palpitations and dizziness that started this morning following a night of studying. The student is very upset that this is happening because the final exams are the following day. The cardiac monitor shows a heart rate of 110, regular rhythm with occasional premature ventricular complexes. The nurse explains to the student that this can happen in healthy hearts and is usually caused by stimulation of: -Parasympathetic nervous system -Sympathetic nervous system -Atrial ectopic foci -Vagal nerve

-Sympathetic nervous system

Which type of pacing involves the placement of large patch electrodes on the anterior and posterior chest wall that can be connected by a cable to an external pulse generator? -Transcutaneous -Transvenous -Permanent -Epicardial

-Transcutaneous

A client with supraventricular tachycardia has received a dose of verapamil to slow the heart rate. Which explanation describes the effect of this drug on the heart? -Slows the sinoatrial (SA) node pacemaker and inhibits conduction in the atrioventricular (AV) node -Blocks the fast sodium channels -Blunts the effect of the sympathetic nervous system stimulation on the heart -Reduces periods of cardiac refraction

-Slows the sinoatrial (SA) node pacemaker and inhibits conduction in the atrioventricular (AV) node

Torsade de pointes is a specific type of polymorphic ventricular tachycardia in which the polarity of the QRS complex swings between positive and negative, often on a beat-to-beat basis. It is the result of the long QT syndrome and can cause sudden cardiac death. Which medication is not linked to torsade de pointes as a causative agent? -Verapamil -Procainamide -Digitalis -Tetracycline

-Tetracycline

A client who will be undergoing a Holter monitor examination would be given which instruction? -"Keep a diary of your activities and symptoms throughout the examination." -"Wear clothing that you can exercise in during the test." -"Lay very still during the procedure for an accurate reading." -"You will need to have an intravenous injection prior to the start of the test."

-"Keep a diary of your activities and symptoms throughout the examination."

A nurse is observing a client's cardiac status by telemetry monitoring. On the monitor, the P wave changes shape and an impulse frequently occurs before the next expected sinoatrial (SA) node impulse. The nurse interprets this rhythm by stating: -"The client is experiencing premature atrial contractions (PACs)." -"The client is experiencing a junctional rhythm." -"The client is in normal sinus rhythm." -"The client is experiencing premature ventricular contractions."

-"The client is experiencing premature atrial contractions (PACs)."

A client has a myocardial infarction (MI) that has damaged the right atrium, which results in interference with the SA node. The compensatory mechanism, the AV node, becomes the pacemaker of the heart and beats how many times per minute? -10 to 20 beats/minute -21 to 30 beats/minute -45 to 50 beats/minute -65 to 70 beats/minute

-45 to 50 beats/minute

Paroxysmal supraventricular tachycardia arises from which form of reentry? -Atrioventricular (AV) nodal -Bundle of His nodal -Orthodromic -True

-Atrioventricular (AV) nodal

A group of nursing students is discussing ventricular dysrhythmias and one student is unsure why a client with frequent premature ventricular complexes (PVCs) has an irregular radial pulse. One of the other students explains that premature ventricular complexes often do not produce a palpable pulse due to: -weakness of the ventricle. -decreased ventricular filling time. -ventricular compensatory pause. -recurrent ventricular pathways.

-decreased ventricular filling time.

An 80-year-old male client arrives for his yearly physical without any complaints, and following the checkup the physician explains that he has noted atrial fibrillation (AF) on the client's ECG. Before the physician can explain the disorder, the client becomes very upset and states he thinks he is going to die. The physician explains that atrial fibrillation involves the top chambers of the heart and that: -many people live with atrial fibrillation without even knowing they have it. -atrial fibrillation is a disorganized ventricular rhythm with recurrent circuits. -the client will be placed on anticoagulants immediately. -the client will experience severe palpitations.

-many people live with atrial fibrillation without even knowing they have it.

A nurse educator is explaining normal cardiac conduction and action potentials to a nursing cohort. How can the nurse best describe the term "slow response" (calcium current) to the students? -"The calcium current provides for the binding of intracellular calcium for the repolarization of electrical activity." -"It facilitates the entrance of calcium needed for cardiac muscle contraction." -"The calcium current provides for the entrance of calcium that -stimulates the AV node." -"It facilitates the entrance of calcium for the excitation-contraction mechanism that couples the electrical activity with muscle contraction."

-"It facilitates the entrance of calcium for the excitation-contraction mechanism that couples the electrical activity with muscle contraction."

A nurse is caring for a client with persistent atrial fibrillation (AF) unresponsive to antiarrhythmic therapy. Prior to an elective cardioversion, the nurse anticipates which intervention? -Administration of anticoagulants -Cardiac catheterization -Initiation of cardiac rehabilitation -Insertion of a temporary pacemaker

-Administration of anticoagulants

The client is diagnosed with a respiratory sinus dysrhythmia. Which electrocardiogram pattern correlates to this finding? -An increase in heart rate with inspiration and slowing with expiration -Pauses in the sinoatrial node firing with increased respiration -Changes in heart rate when the respiratory rate drops -Increase in the heart rate with an increased respiratory rate above 22 breaths/min

-An increase in heart rate with inspiration and slowing with expiration

Which cardiac drug classification decreases sympathetic outflow to the heart and is the is the cornerstone of therapy for catecholaminergic polymorphic ventricular tachycardia (CPVT)? -Beta-adrenergic blockers -Sodium channel blockers -Potassium blockers -Calcium channel blockers

-Beta-adrenergic blockers

Which antiarrhythmic medication works by blunting the effect of sympathetic nervous system stimulation on the heart? -Beta-blockers, such as metoprolol -Calcium channel blockers, such as verapamil -Sodium channel blockers, such as lidocaine -Antianginal drugs, such as nitroglycerin

-Beta-blockers, such as metoprolol

The nurse is caring for a client who suffered a massive myocardial infarction and is scheduled for an immediate permanent pacemaker insertion due to severe ischemia and damage to both SA and AV nodes. The nurse would expect which of the following? -Bradycardia with rate of 20-40 -Severely elevated diastolic pressure -Tachycardia with rate between 100-120 -Heart rate between 40-60

-Bradycardia with rate of 20-40

The nurse explains to a client with a history of unstable angina undergoing knee replacement surgery that it is important to monitor the cardiac rhythms to ensure early detection of which potential complication? Select all that apply. -Cardiac muscle ischemia -Tachyarrhythmias -Bradyarrhythmias -Irregular rhythms -Decreased ejection fraction

-Cardiac muscle ischemia -Tachyarrhythmias -Bradyarrhythmias -Irregular rhythms

Which class of cardiac antiarrhythmic drugs extends the action potential and refractoriness of the heart's contraction? -Class III -Class IV -Class II -Class I

-Class III

In children, what is sick sinus syndrome most commonly associated with? -Congenital heart defects prior to corrective cardiac surgery -Destruction of the sinoatrial node -Congenital heart defects following corrective cardiac surgery -Destruction of the atrioventricular node

-Congenital heart defects following corrective cardiac surgery

A client's electrocardiogram monitor begins to sound an alarm and shows sustained ventricular fibrillation. The client is unconscious and without a pulse. Which priority intervention should the nurse take? -Defibrillate the client -Administer IV push atropine -Perform synchronized cardioversion -Notify the client's attending physician

-Defibrillate the client

A 31-year-old woman with a congenital heart defect reports episodes of lightheadedness and syncope, with occasional palpitations. A resting ECG reveals sinus bradycardia, and she is suspected to have sick sinus syndrome. Which diagnostic method is the best choice to investigate the suspicion? -Signal-averaged ECG -Exercise stress testing -Electrophysiologic study -Holter monitoring

-Holter monitoring

Nursing students who are studying for their upcoming cardiac exam are discussing how the heart could possibly continue to beat once removed from the body. One of the students explains that this phenomenon is directly related to automaticity. What is automaticity? -Inherent spontaneous action-potential -Inherent discharge rate of 60-80 -Inherent low-impulse conductivity -Inherent discharge rate of 40-60

-Inherent spontaneous action-potential

A nurse is monitoring a client with sick sinus syndrome who is experiencing lightheadedness, dizziness, and syncope. Which treatment will the nurse anticipate for this client? -Insertion of a pacemaker -Administration of beta-blockers -Synchronized cardioversion -Defibrillation

-Insertion of a pacemaker

Respiratory sinus dysrhythmia is considered a more optimal rhythm than a rhythm where all RR intervals are equal. In respiratory sinus dysrhythmia, what is the variation in cardiac cycles related to? -Intra-abdominal pressure changes that occur with respiration -Intrathoracic pressure changes that occur with respiration -Intra-abdominal pressure changes due to vagal nerve stimulus -Intrathoracic pressure changes due to inadequate oxygenation

-Intrathoracic pressure changes that occur with respiration

A 28-year-old client is admitted to the hospital for severe dehydration following a marathon, with fatigue the only complaint. Admission vital signs include a heart rate of 38, blood pressure 98/60, RR 16. Cardiac monitor reveals regular QRS complexes preceded by normal P waves. Which of the following does the nurse determine is the most likely cause for the bradycardia? -Potential lethal dysrhythmia -Large stroke volume -Reduced cardiac output -Prolonged Q-T syndrome

-Large stroke volume

Sick sinus syndrome is suspected in the case of a child who is postoperative following cardiac surgery. Which nursing action is most appropriate? -Reassure the child's family that the condition is usually self-limiting. -Facilitate an exercise stress test as ordered. -Monitor the child's ECG for bradycardia. -Review the results of the child's echocardiogram.

-Monitor the child's ECG for bradycardia.

A nurse notes that the PR interval on a client's electrocardiogram tracing is 0.22 seconds. Which action should the nurse take? -Call the health care provider. -Administer atropine and place external pacemaker on the client. -Administer oxygen via nasal cannula. -Monitor the client and document the findings.

-Monitor the client and document the findings.

A client has been admitted after being resuscitated from a cardiac arrest. The client is prescribed Class I for electrocardiogram monitoring. What type of monitoring will the nurse perform for this client? -Continuous cardiac monitoring -Intermittent cardiac monitoring -Monitoring only with chest pain -No monitoring is indicated

-Monitoring only with chest pain

ECG monitoring has been found to be more sensitive than a client's report of symptoms when identifying transient ongoing myocardial ischemia. Why is this? -Most ECG-detected ischemic events are clinically silent. -The ECG can look at ischemic events from different directions. -ECG monitoring is reliable only when the client remains still. -Most ECG-detected ischemic events cause a great deal of pain.

-Most ECG-detected ischemic events are clinically silent.

The nurse assesses the electrocardiogram for depolarization of the atria. What portion of the ECG will the nurse be assessing? -P wave above the baseline -Q wave below the baseline -T wave above the baseline -U wave above the baseline

-P wave above the baseline

A nurse is monitoring the electrocardiogram (ECG) of a client with a recent right ventricular infarction. The ECG reveals a first-degree atrioventricular (AV) block, which is characterized by: -PR interval >0.20 seconds -ST segment elevation -Absent P wave -T-wave inversion

-PR interval >0.20 seconds

A monitored hospitalized client with a pulmonary embolism has been in atrial fibrillation (AF) for 4 days. The nurse observes the rhythm spontaneously convert to a normal sinus rhythm. Which form of AF is this? -Chronic -Permanent -Paroxysmal -Persistent

-Paroxysmal

A client experiencing a sinus arrest would demonstrate which symptom or finding? -Heart rate of greater than 100 beats/min -P-wave that occurs more frequently than expected -Prolonged periods of asystole demonstrated on an electrocardiogram -Spontaneous persistent sinus bradycardia

-Prolonged periods of asystole demonstrated on an electrocardiogram

The nurse is interpreting an electrocardiogram of a 65-year-old woman. Which should the nurse recognize as representing ventricular depolarization? -P wave -QRS complex -T wave -ST segment

-QRS complex

An intensive care nurse caring for a client who is diagnosed with an anterior wall myocardial infarction (MI) notes frequent premature ventricular complexes on the ECG monitor and is concerned the client could develop a lethal dysrhythmia if one of the premature ventricular complexes fires on which phase of the cardiac action potential? -Premature action potential phase -Phase 1 depolarization begins -Phase 2 depolarization plateaus -Relative refractory period ends

-Relative refractory period ends

What is the correct sequence for the generation of electrical impulses in the heart causing ventricular contraction? -SA node - AV node - bundle of His - bundle branches - Purkinje fibers -AV node - SA node - bundle of His - bundle branches - Purkinje fibers -SA node - AV node - bundle branches - Purkinje fibers - bundle of His -AV node - bundle of HIS - bundle branches - SA node - Purkinje fibers

-SA node - AV node - bundle of His - bundle branches - Purkinje fibers

A nurse witnesses an older adult woman sitting outside who suddenly faints and is helped to the ground by family. She is awake, although confused, heart rate 130, RR 28. The woman states that all of a sudden she felt dizzy, but denies other symptoms. She says that her husband died last week and she has been very upset. The nurse determines that which of the following is the most likely reason for the syncopal episode? -Congestive heart failure -Blood loss -Severe anxiety -Severe pain

-Severe anxiety

A nurse is explaining the conduction system of the heart to a client who is experiencing an dysrhythmia. Which would be the most accurate explanation? -Sinoatrial node (SA), internodal pathways, atrioventricular (AV) node, AV bundle, Purkinje fibers -Internodal pathways, atrioventricular (AV) node, sinoatrial node (SA), AV bundle, Purkinje fibers -Sinoatrial node (SA), atrioventricular (AV) bundle, internodal pathways, AV node, Purkinje fibers -AV node, sinoatrial node (SA), atrioventricular (AV) bundle, Purkinje fibers, intermodal pathways

-Sinoatrial node (SA), internodal pathways, atrioventricular (AV) node, AV bundle, Purkinje fibers

A 28-year-old marathon runner comes to the clinic to obtain a physical exam for a new job. The nurse assesses a regular pulse rate of 52 beats per minute (bpm). Which common dysrhythmia is the nurse aware this client most likely has related to maintaining a large stroke volume? -Sinus bradycardia -Sinus tachycardia -Atrial fibrillation -Atrial flutter

-Sinus bradycardia

A client is seen in the emergency department complaining of chest discomfort, productive cough, and a fever of over 101°F (38.3°C) for 3 days. The nurse performs an electrocardiogram and observes a rate of 110 beats per minute (bpm) with a normal P wave and a PR interval of 0.12 second preceding each QRS complex. What does the nurse determine the rhythm to be? -Third-degree heart block -Atrial flutter -Sick sinus syndrome -Sinus tachycardia

-Sinus tachycardia

Which dysrhythmia is considered to be the most fatal and requires immediate treatment? -Ventricular fibrillation -Premature ventricular contractions -Premature atrial contractions -Atrial flutter

-Ventricular fibrillation

A client presents with uncharacteristic chest pain, and his ECG reveals T-wave elevation. This finding suggests an abnormality with which aspect of the cardiac cycle? -Atrial depolarization -Ventricular depolarization -Ventricular repolarization -Depolarization of the AV node

-Ventricular repolarization

A college student is in pre-op area prior to knee surgery. The nurse attaches the cardiac monitor and notes a gradual lengthening and shortening between the R waves. The nurse realizes that this rhythm is most often found in people with healthy hearts. This rhythm is a respiratory: -AV nodal dysrhythmia. -first-degree block. -atrial dysrhythmia. -sinus dysrhythmia.

-sinus dysrhythmia.

A client arrives at the emergency room with dizziness and a near syncopal episode. Vital signs include a heart rate of 46 beats/min and blood pressure of 86/50 mm Hg. The cardiac monitors show regular rhythm as above. The client states the health care provider has been running blood work to rule out hypothyroidism. Based on the rhythm, what does the nurse report the client has? -Wolff-Parkinson-White syndrome -symptomatic third-degree atrioventricular (AV) block -symptomatic bradyarrhythmia -symptomatic tachyarrhythmia

-symptomatic bradyarrhythmia