Chapter 28 PrepU

A client is having an electrocardiogram (ECG) performed for a routine physical examination. The client states he has been feeling well and has no reports of pain or discomfort. The nurse observes a regular atrial and ventricular rate of 64, a PR interval of 0.26, and a QRS of 0.06 sec. The nurse determines that this rhythm is called:

First-degree heart block

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

Which antiarrhythmic medication works by blunting the effect of sympathetic nervous system stimulation on the heart?

Beta-blockers, such as metoprolol

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?

Ventricular repolarization

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

A nursing student is studying the properties of cardiac rhythm to better understand what causes dysrhythmias to occur. The student begins to understand that there is a programmed ability for certain cells to conduct impulses. Interruption in this ability can result in abnormalities of cardiac rate and rhythm; this property would be:

conductivity.

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)."

A client has had a myocardial infarction (MI) that damaged the right atrium, which has interfered with the SA node. The compensatory mechanism, the AV node, becomes the pacemaker of the heart and beats how many times/minute?

45 to 50 beats/min

Assuming that they have not responded to drug therapy, which client is likely to be the best candidate for surgical cardiac ablation?

A 72-year-old woman who has recurrent paroxysmal supraventricular tachycardia

A client is admitted to the hospital with severe bradycardia, heart rate in low to upper 40s, after contracting Lyme disease. She asks the nurse why the heart rate is so slow. The most accurate response would be a possible disassociation between the atria and ventricles due to:

AV nodal block

A client with a history of angina has presented to the emergency department with uncharacteristic chest pain. The electrocardiogram (ECG) reveals ST segment depression. Which test is most effective for identifying transient ongoing myocardial ischemia?

Continuous ECG monitoring

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?

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

An older adult client with a past medical history of diabetes type II and myocardial infarction (MI) is admitted with sudden shortness of breath, palpitations, irregular apical pulse with no pattern, heart rate of 130 and blood pressure of 100/60. The nurse suspects atrial fibrillation (AF) for which reasons? Select all that apply.

Palpitations Irregular rhythm Tachycardia

Considering the PQRST complex of an electrocardiogram (ECG), which letter designation represents atrial depolarization?

P wave

Following angioplasty for a blocked coronary artery following a myocardial infarction, a client is prescribed serial 12-lead ECGs for three days. On the second day, the nurse notices a distinct difference in the QRS morphology from the previous ECG. Which is the best action for the nurse to take?

Repeat ECG with proper lead placement.

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

Which of the following is called the pacemaker of the heart?

Sinoatrial (SA) node

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

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:

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

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.

Which degree of "heart block" results in decreased cardiac output and fainting?

Third-degree

Paroxysmal supraventricular tachycardia arises from which form of reentry?

Atrioventricular (AV) nodal

A nurse is caring for four clients. Which client is most at risk for atrial fibrillation (AF)?

An older adult man who is 2 days postcoronary artery bypass surgery

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 bearing down while having a bowel movement."

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?

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

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."

When explaining a new diagnosis of complete heart block to a client and family, the nurse should include which statement?

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

When a client has a recurrent, life-threatening arrhythmia originating either supraventricularly or ventricularly, ablation therapy is an option for treatment. What does ablation therapy do?

Isolates and destroys arrhythmogenic cardiac tissue

A client has been diagnosed with atrial flutter. Which assessment finding correlates with this diagnosis?

An atrial heart rate above 240 beats/min

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

Which classification of antiarrhythmic drugs acts by inhibiting the potassium current and repolarization, thereby extending the action potential and refractoriness?

Class III

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

Brugada syndrome, an autosomal dominant disorder, manifests in adulthood as ST-segment elevation, right bundle branch block, and susceptibility to ventricular tachycardia. In Brugada syndrome, the timing of cardiac events is significant. When do these cardiac events typically occur?

During sleep or rest

A client has been diagnosed with runs of intermittent ventricular tachycardia where the client loses consciousness and needs to be stimulated to recovery. Knowing this history, the nurse will educate the client about which treatment intervention/procedure that will depolarize the heart to allow the sinoatrial node to regain control of the heart?

Education involving automatic implantable cardioverter-defibrillators implantation

The nurse is assisting a client who had a myocardial infarction 2 days ago during a bath. The client suddenly lost consciousness and the nurse was unable to feel a pulse. Cardiopulmonary resuscitation was begun and the client was connected to the monitor with a gross disorganization without identifiable waveforms or intervals observed. What is a priority intervention at this time?

Immediate defibrillation

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

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?

Intrathoracic pressure changes that occur with respiration

Which client will the nurse prioritize to assess first?

client with sinus arrest

A nurse notes that the PR interval on a client's electrocardiogram tracing is 0.22 seconds. Which action should the nurse take?

Monitor the client and document the findings.

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 nurse assesses the electrocardiogram for depolarization of the atria. What portion of the ECG will the nurse be assessing?

P wave above the baseline

A nurse is observing the cardiac monitor of a client that suddenly displays a regular rhythm with absent P waves and a heart rate of 200 beats/min. The nurse interprets these findings as resulting from:

Paroxysmal supraventricular tachycardia

The nurse is evaluating a client with cardiac problems and notes that the client's peripheral pulse is different than the apical pulse. To which physiologic response would the nurse attribute the difference in rates?

Premature beats not following normal conduction pathways

A client experiencing a sinus arrest would demonstrate which symptom or finding?

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?

QRS complex

A client with a 2-week history of hyperthyroidism due to a virus is admitted for nonemergent cardioversion. The client states that she has been experiencing intermittent episodes of palpitations over the past week along with shortness of breath and fatigue. The nurse attaches the client to a cardiac monitor and notes that the client is in normal sinus rhythm with frequent episodes of atrial fibrillation. The nurse anticipates which of the following to be ordered prior to the cardioversion to avoid a possible stroke?

Transesophageal echocardiography

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?

Ventricular repolarization

The nursing student is studying normal cardiac physiology and how the electrical stimulation should affect the mechanical function. The student determines that the atria are given time to fully empty at which point on the ECG tracing below?

line after first hump

An intensive care unit nurse is caring for a client who suffered a myocardial infarction involving the anterior wall, and notes a change in the cardiac rhythm. The rhythm has a PR interval that does not change, but there are twice as many P waves as there are R waves. The nurse prepares for a temporary pacemaker insertion because the client has developed:

second-degree, type 2 AV block.

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:

sinus dysrhythmia.

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?

sinus tachycardia

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?

symptomatic bradyarrhythmia