Chapter 28: Disorders of Cardiac Conduction and Rhythm

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.

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 brachycardia

Which of the following occurs during repolarization?

Positively charged K+ moves outward across the cell membrane

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

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 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 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 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."

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

Beta-blockers, such as metoprolol

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

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

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

An atrial heart rate above 240 beats/min

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

Paroxysmal supraventricular tachycardia arises from which form of reentry?

Arterioventricular (AV) nodal

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

An exercise stress test challenges the heart to respond to the increased demands of exercise in a controlled and monitored environment. Not only do exercise stress tests show changes in heart rate, blood pressure, and perceived level of exercise, but they have also been found useful in determining:

ECG ischemic-type ST-segment changes

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

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

P wave

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 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?

Paroxysmal

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

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

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 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

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.

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 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

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

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 is scheduled to have a Holter monitor for 48 hours to detect disturbances in conduction. Which action is important for the nurse to tell the client to ensure accuracy in correlating dysrhythmias with symptoms?

It is important to keep a diary of activities and symptoms.

Which client will the nurse prioritize to assess first?

The client with sinus arrest

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 arrhythmia.

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."

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

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

A client with a past medical history of congestive heart failure is admitted to the hospital with severe palpitations and a heart rate of 170, blood pressure 88/60. Home medications include digoxin, a loop diuretic, and a baby aspirin. The physician has diagnosed the client with focal atrial tachycardia and is discussing the treatment options with the client. Which action would most likely be ordered first?

Correction of the underlying cause