Cardiac Rhythms & Dysrhythmias

The nurse observes the rhythm strip of a patient sitting up in bed and talking. The strip shows ventricular tachycardia (VT). What action should the nurse take? 1) Perform rapid defibrillation 2) Palpate the patient for a pulse 3) Take the patient's blood pressure 4) Start cardiopulmonary resuscitation (CPR)

2) Palpate the patient for a pulse The rhythm strip characterizes ventricular tachycardia (VT). Therefore the first step is to palpate the pulse. The treatment for VT with a pulse differs greatly than for VT without a pulse. If the VT is monomorphic and the patient has a pulse and has preserved left ventricular function, IV drugs are used. VT without a pulse is a life-threatening situation; rapid defibrillation and CPR are the first lines of treatment in this scenario. The nurse can take the patient's blood pressure after the presence of a pulse has been determined.

A patient undergoing treatment for dysrhythmia is provided with a Holter monitor. What information should the nurse include in the patient teaching about the test? Select all that apply. 1) The patient should activate the monitor when experiencing symptoms. 2) The monitor records the electrocardiogram (ECG) when the patient is ambulatory. 3) The patient should record activities and any symptoms in a diary. 4) New technology using smart phone apps can obtain and save electrocardiogram (ECG) recordings. 5) The monitor records the electrocardiogram (ECG) when the patient performs daily activities.

2) The monitor records the electrocardiogram (ECG) when the patient is ambulatory. 3) The patient should record activities and any symptoms in a diary. 4) New technology using smart phone apps can obtain and save electrocardiogram (ECG) recordings. 5) The monitor records the electrocardiogram (ECG) when the patient performs daily activities. The Holter monitor continuously records the ECG while the patient is ambulatory and performing daily activities. The patient should keep a diary and record activities and any symptoms. New technology using smart phone apps can obtain and save electrocardiogram (ECG) recordings and even detect some dysrhythmias. Exercise treadmill testing evaluates the patient's heart rhythm during exercise.

The nurse is preparing to perform an electrocardiogram (ECG) on a patient. The nurse observes artifact on the monitor. What are possible causes of the artifact? Select all that apply. 1) The patient has dry skin. 2) The patient is shivering. 3) The conductive gel is moist. 4) Electrical interference is present. 5) The leads and electrodes are not secure.

2) The patient is shivering. 4) Electrical interference is present. 5) The leads and electrodes are not secure. Muscle activity caused by shivering of the patient, electrical interference, or loose leads and electrodes can cause distorted baseline and waveforms called artifact on the electrocardiogram (ECG). Oily skin is wiped dry with alcohol to prepare the patient for ECG. Electrodes may have to be replaced if conductive gel has dried out.

The nurse is reviewing discharge instructions with a patient that received an implantable cardioverter-defibrillator (ICD). Which patient statement indicates the need for further teaching? 1) "I should avoid flying for three years." 2) "I should avoid direct blows to the ICD site." 3) "I should avoid standing near antitheft devices in doorways." 4) "I should avoid large magnets and strong electromagnetic fields."

1) "I should avoid flying for three years." Flying is not contraindicated in a patient with an implantable cardioverter-defibrillator (ICD). To ensure safety, the patient should inform airport security about the presence of the ICD at the airport because it may set off the metal detector. The patient should avoid direct blows to the ICD site to reduce pressure at the site. Electric and magnetic signals from antitheft devices and strong electromagnetic fields can affect ICD functioning.

A patient with a newly inserted pacemaker receives discharge instructions from the nurse. Which patient statement indicates that further teaching is required? 1) "I should avoid using microwave ovens." 2) "I should avoid standing near antitheft devices." 3) "I should avoid direct blows to the pacemaker site." 4) "I should avoid close proximity to high-output electric generators."

1) "I should avoid using microwave ovens." Microwaves do not interfere with a pacemaker's function and can be used safely. Electric signals from antitheft devices can affect pacemaker functioning. The patient should avoid direct blows to the pacemaker site to reduce pressure at the site. Electric signals from high-output electric generators can move the pacemaker from its position and affect its functioning.

The registered nurse is reviewing a wireless electrocardiogram (ECG) monitoring system with a nursing student. Which statement made by the student indicates the need for further teaching? 1) "It fails to record the postevent portion of the ECG." 2) "It can automatically save the preevent portion of the ECG." 3) "It continuously monitors and interprets the findings of patients." 4) "It sends an alert when a patient's measurements fall outside the set parameters."

1) "It fails to record the postevent portion of the ECG." The wireless ECG monitoring systems continue to record the postevent portion of ECG and send it to the healthcare provider. The wireless ECG monitoring systems can automatically save the preevent portion of the ECG, continuously monitor and interpret the findings of a patient, and send an alert when patient rhythm or measurements fall outside the set parameters.

A patient has sought care following a syncopal episode of unknown etiology. The nurse anticipates that what will be included in the patient's treatment plan? 1) A head-up tilt-test 2) Intravenous (IV) B-adrenergic blocker 3) Pacemaker insertion 4) Antiplatelet therapy

1) A head-up tilt-test In patients without structural heart disease, the head-up tilt-test is a common component of the diagnostic workup following episodes of syncope. IV B-blockers are not indicated, although an IV infusion of low-dose isoproterenol may be started in an attempt to provoke a response if the head-up tilt-test did not produce a response. Addressing pacemakers is premature and inappropriate at this stage of diagnosis. There is no data to support the initiation of anti platelet therapy.

A patient on a cardiac unit is shivering. What does the nurse expect to see on the patient's ECG tracing? 1) Artifact 2) Asystole 3) Atrial flutter 4) Junctional dysrhythmia

1) Artifact An artifact is a distortion of the baseline and waveforms seen on the electrocardiogram (ECG). If the patient is shivering or shows any muscle activity, accurate interpretation of the heart rhythm is difficult and artifacts can occur on the monitor. Asystole is the absence of all cardiac electrical activity. Atrial flutter occurs in chronic lung disease or hypertension. Junctional dysrhythmias are associated with an electrolyte imbalance or rheumatic heart disease.

The nurse responds to a cardiac monitor alarm and notes that atrial flutter has developed on a patient's electrocardiogram (ECG). The nurse visualizes the patient's room and notes that the patient is awake and talking. Which action should the nurse take? 1) Assess the patient for dyspnea 2) Initiate cardiopulmonary resuscitation (CPR) 3) Prepare for synchronized cardioversion 4) Place the patient in the Trendelenburg position

1) Assess the patient for dyspnea Because the patient is awake and responsive, the next action is to assess the patient for stability and the possible cause of the dysrhythmia. The nurse should focus the assessment on vital signs, such as blood pressure, heart rate, and respiratory status. Initiating cardiopulmonary resuscitation is only appropriate for a patient that is in respiratory or cardiac arrest. Synchronized cardioversion would only be an option if the patient were unstable. The Trendelenburg position is inappropriate for a patient with atrial flutter.

A patient is hospitalized for treatment of symptoms associated with a junctional escape rhythm, including a heart rate (HR) of 45 beats/min. What does the nurse expect to be prescribed for this patient? 1) Atropine 2) Propanolol 3) Amiodarone 4) Cardioversion

1) Atropine A junctional escape rhythm is a delayed heartbeat that originates from an ectopic focus somewhere in the atrioventricular junction, not from the atrium. If a patient has symptoms with a junctional escape rhythm, atropine can be used; it will increase the patient's heart rate. Propranolol and amiodarone would not be appropriate for this patient; they cause bradycardia. Cardioversion should not be used for junctional dysrhythmias.

The nurse recalls that the heart's ability to initiate an impulse spontaneously and continuously is known as what property of heart cells? 1) Automaticity 2) Excitability 3) Conductivity 4) Contractibility

1) Automaticity Automaticity is the heart's ability to initiate an impulse spontaneously and continuously. Excitability is the ability to be electrically stimulated. Conductivity is the ability to transmit an impulse along a membrane in an orderly manner. Contractility is the ability to respond mechanically to an impulse.

The nurse is caring for a patient that has been advised to have a permanent pacemaker implanted. What are indications for a permanent pacemaker? Select all that apply. 1) Cardiomyopathy 2) SA node dysfunction 3) Coronary angioplasty 4) Drug therapy that may cause bradycardia 5) Third-degree atrioventricular (AV) block

1) Cardiomyopathy 2) SA node dysfunction 5) Third-degree atrioventricular (AV) block A permanent pacemaker helps to maintain the normal cardiac pace and is implanted within the body. The power source of such a device is placed subcutaneously, usually over the pectoral muscle on the patient's nondominant side. The permanent pacemaker is used in cardiomyopathy, SA node dysfunction, and third-degree AV block when the dysfunction of the electrical pathways is assumed to be permanent or irreversible. A temporary pacemaker may be required during coronary angioplasty and during drug therapy that may cause bradycardia. To maintain adequate cardiac rhythms during postoperative recovery and as a prophylactic measure after open heart surgery, temporary pacemakers are used.

The nurse teaches a group of nursing students about telemetry monitoring. The nurse should provide information that the steps for applying electrodes should be performed in what order? -Affix the electrodes -Clip excessive hair with scissors -Monitor for artifact -Gently rub the skin with dry gauze

1) Clip excessive hair with scissors 2) Gently rub the skin with dry gauze 3) Affix the electrodes 4) Monitor for artifact The first stop during the measurement of an ECG is to remove excess hair on the skin. The presence of hair may not facilitate the proper adherence of electrodes to the skin. This could interfere with the recording of the cardiac impulses. It is followed by wiping the skin with alcohol to remove dirt and oil, and gently rubbing with gauze until the skin becomes pale pink. Wiping of the skin is followed by attaching the electrodes to the patient at the designated areas. Artifact may occur for various reasons. This indicates deformity of baseline and waveforms on electrocardiograph.

A patient reports a new onset of jaw pain. The nurse obtains the following electrocardiogram (ECG) tracing. What action should the nurse take? 1) Contact the primary health care provider 2) Administer hydrocodone 3) Place the patient in a Trendelenburg position 4) Recognize the ECG changes as indicative of digitalis toxicity

1) Contact the primary health care provider The ECG tracing is showing ST elevation indicative of myocardial infarction (MI). The primary health care provider should be notified immediately so appropriate interventions can be prescribed. Morphine sulfate is the drug of choice for a patient experiencing an acute MI. Whenever possible, the patient experiencing an MI should be placed in a position promoting respirations. The Trendelenburg position inhibits respirations. Digoxin toxicity is characterized by ST segment depression, not elevation.

A patient in asystole is likely to receive which drug treatment? 1) Epinephrine and vasopressin 2) Lidocaine and amiodarone 3) Digoxin and procainamide 4) B-adrenergic blockers and dopamine

1) Epinephrine and vasopressin Treatment of asystole consists of CPR with initiation of ACLS measures. These include definitive drug therapy with epinephrine and/or vasopressin, and intubation. Lidocaine and amiodarone are used for premature ventricular contractions (PVCs). Digoxin and procainamide are used for ventricular rate control. B-adrenergic blockers are used to slow heart rate and dopamine is used to increase heart rate.

The nurse is monitoring a patient in the intensive care unit. Which are the most common leads selected for continuous monitoring? Select all that apply. 1) Lead II 2) Lead III 3) Lead V 1 4) Lead V 6 5) Lead aVR

1) Lead II 3) Lead V 1 An electrocardiogram is a graphical representation of the electrical impulses produced in the heart. It involves the use of 12 leads. Lead II and lead V1 are commonly used for continuous monitoring of the cardiac impulses. The use of lead III, lead V6, and lead aVR are also a part of the normal 12-lead electrocardiogram, but are not usually used for continuous monitoring.

A patient with a heart rate of 180 beats/minute has a regular heart rhythm, normal P waves, and normal PR intervals. The nurse expects to see what QRS complex shape on the patient's ECG tracing? 1) Normal 2) Not measurable 3) Wide and distorted 4) Abnormally shaped

1) Normal A normal P wave and normal PR interval in electrocardiogram (ECG) and the heart rate of 180 beats/minute indicates sinus tachycardia. The patient with sinus tachycardia generally shows normal QRS complexes. The QRS complex will not be measurable in the patient with ventricular fibrillation. The QRS complex will be wide and distorted or abnormally shaped in the ECG of a patient who has ventricular tachycardia or premature ventricular contractions. The P wave in these patients will not usually be visible and the PR interval will not be measurable.

A patient is experiencing unifocal premature ventricular contractions (PVCs). The nurse expects to find what ECG characteristics? Select all that apply. 1) P wave that is not visible 2) PR interval that is not measurable 3) Wide and distorted QRS complex 4) Normal T wave 5) PVCs that have the same shape

1) P wave that is not visible 2) PR interval that is not measurable 3) Wide and distorted QRS complex 5) PVCs that have the same shape A premature ventricular contraction (PVC) is a contraction that results from an ectopic focus in the ventricles. In other words, the QRS complex occurs prematurely. The P wave is rarely visible and is usually hidden in the PVC. The PR interval is not measurable. The QRS complex is wide and distorted in shape compared with a QRS complex coming down a normal conduction pathway. PVCs that arise from the same foci appear the same in shape and are called unifocal PVCs. The T wave is generally normal.

The nurse has obtained a rhythm strip from a patient's telemetry monitor. Which description of the electrocardiogram (ECG) is correct? 1) Sinus tachycardia 2) Sinus bradycardia 3) Ventricular fibrillation 4) Ventricular tachycardia

1) Sinus tachycardia This rhythm strip shows sinus tachycardia because the rate on this strip is above 101, and it displays normal P wave, PR interval, and QRS complex. Sinus bradycardia would look similar to sinus tachycardia but with a rate less than 60 beats/minute. Ventricular fibrillation does not have a measurable heart rate, PR interval, or QRS, and the P wave is not visible and the rhythm is irregular and chaotic. Ventricular tachycardia has a rate of 150 to 250 beats/minute, with a regular or irregular rhythm and P waves occurring independently of the QRS complex.

A patient is hospitalized following a 3-day history of heart palpitations and dizziness. The patient's electrocardiogram (ECG) shows the following rhythm. The nurse identifies that the patient is at risk for what? 1) Stroke 2) Type 2 diabetes 3) Myocardial infarction 4) Sudden cardiac death

1) Stroke A risk of atrial fibrillation is clot formation in the atria caused by altered blood flow through the heart. If the clot forms on the right side of the heart, it can travel to the lungs, causing a pulmonary embolism. If the clot forms on the left side of the heart, the risk of it traveling to the brain, causing a stroke or an embolism to other arteries in the body. The risk of an embolus is particularly high when the patient converts back to a normal sinus rhythm. To reduce the risk of clot formation in the heart, most patients with chronic atrial fibrillation are on some type of anticoagulation. Coumadin (Warfarin) often is prescribed.

The nurse monitors the electrocardiogram (ECG) of a patient diagnosed with acute coronary syndrome. The patient's baseline rhythm is sinus rhythm. Which additional ECG findings are most suggestive of myocardial infarction? Select all that apply. 1) T-wave inversion 2) Pathologic Q wave 3) Elevated ST segment 4) Depressed ST segment 5) Premature atrial contractions

1) T-wave inversion 2) Pathologic Q wave 3) Elevated ST segment Typical ECG changes that are seen in myocardial infarction include ST-segment elevation (not depression), T-wave inversion, and a pathologic Q wave. The patient will not have premature atrial contractions.

What does the T wave in an electrocardiogram (ECG) represent? 1) Time for ventricular repolarization 2) Time for depolarization of both ventricles 3) Time between ventricular depolarization and depolarization 4) Time for the passage of the electrical impulse through the atrium

1) Time for ventricular repolarization The electrocardiogram is commonly used to detect abnormal heart rhythms and to investigate the cause of chest pains. The T wave in the electrocardiogram should be upright; it represents time for ventricular repolarization. Time taken for depolarization of both ventricles is represented by QRS interval. Time between ventricular depolarization and repolarization is represented by ST segment. Time for the passage of the electrical impulse through the atrium is represented by P wave.

Defibrillation is indicated for which dysrhythmia? 1) Ventricular fibrillation 2) Third-degree atrioventricular (AV) block 3) Uncontrolled atrial fibrillation 4) Ventricular tachycardia with a pulse

1) Ventricular fibrillation Defibrillation is always indicated in the treatment of ventricular fibrillation. Pacemakers are the treatment of choice for third-degree heart block. Drug treatments normally are used in the treatment of uncontrolled atrial fibrillation and for ventricular tachycardia with a pulse (if the patient is stable). Otherwise, synchronized cardioversion is used (as long as the patient has a pulse).

A patient states, "I feel tired all the time, and I struggle with activities of daily living." When auscultating the patient's heart rate, the nurse notes disorganization of atrial electrical activity and records a rate of 120 bpm. Which rhythm does the nurse anticipate observing? 1) Asystole 2) Atrial fibrillation 3) Sinus bradycardia 4) Ventricular fibrillation

2) Atrial fibrillation Atrial fibrillation is characterized as irregular. In addition, this rhythm can reduce cardiac output due to the loss of atrial kick and a rapid ventricular rate, causing a reduced exercise tolerance and an elevated heart rate above 100 bpm. The patient will not have a pulse and will not be responsive if the rhythm is ventricular fibrillation or asystole. A patient with sinus bradycardia will have a heart rate less than 60 bpm.

The nurse finds that a patient has an atrial rate of 450 beats per minute and a ventricular rate of 150 beats per minute. What condition is the patient likely experiencing? 1) Atrial flutter 2) Atrial fibrillation 3) Ventricular fibrillation 4) Premature ventricular contractions

2) Atrial fibrillation Atrial fibrillation is characterized by alterations in electrical conductivity of the atrium. The atrial rate is as high as 350 beats per minute to 600 beats per minute. Atrial fibrillation with controlled ventricular response is observed at a ventricular rate of 60 beats per minute to 100 beats per minute. A ventricular rate above 100 beats per minute is considered as atrial fibrillation with uncontrolled ventricular response. The atrial rate and ventricular rate in atrial flutter occur at the ratio of 2:1. The atrial rate is observed between 200 beats per minute to 350 beats per minute and the ventricular rate occurs at 150 beats per minute. Ventricular fibrillation elicits dysrhythmia and P wave and QRS complex cannot be predicted. Premature ventricular contractions elicit dysrhythmia with deflections in the heart rate.

The nurse observing a telemetry monitor notes that a patient that was in sinus rhythm is now in a different rhythm. The electrocardiogram (ECG) now shows no P waves, fine and wavy lines between the QRS complexes, QRS complexes that measure 0.08 sec, and QRS complexes that occur irregularly with a rate of 120 beats/minute. The nurse correctly interprets this rhythm as what? 1) Sinus tachycardia 2) Atrial fibrillation 3) Ventricular fibrillation 4) Ventricular tachycardia

2) Atrial fibrillation Atrial fibrillation is represented on the cardiac monitor by irregular R-R intervals and small fibrillatory (f) waves. There are no normal P waves because the atria are not contracting truly, just fibrillating. Sinus tachycardia is a sinus rate above 100 beats/minute with normal P waves. Ventricular fibrillation is seen on the ECG without a visible P wave, an unmeasurable heart rate, PR, or QRS, and the rhythm is irregular and chaotic. Ventricular tachycardia is seen as three or more premature ventricular contractions (PVCs) that have distorted QRS complexes with regular or irregular rhythm; the P wave usually is buried in the QRS complex without a measureable PR interval.

The nurse provides discharge teaching to a patient that underwent pacemaker implantation in the left chest. What should the nurse include in the instructions? Select all that apply: 1) Showering is permitted as long as care is taken to pat dry the incision site 2) Avoid direct blows to the incision site 3) Raise the left arm above the head frequently, to promote circulation 4) Monitor pulse and inform the health care provider if the heart rate drops below the predetermined rate 5) Microwave ovens are safe to use

2) Avoid direct blows to the incision site 4) Monitor pulse and inform the health care provider if the heart rate drops below the predetermined rate 5) Microwave ovens are safe to use The patient should avoid direct blows to the incision site for safety reasons. The patient should monitor the pulse and inform the cardiologist if it drops below the predetermined rate. Microwave ovens are safe to use and do not interfere with the functioning of the pacemaker. Also, the incision site should be kept dry for four days after implantation, so showering should be avoided. The patient should avoid lifting the arm above the shoulder until approved by the cardiologist, because it might affect the functioning of the pacemaker.

Which property of the cardiac cell aids in responding mechanically to an impulse? 1) Excitability 2) Contractility 3) Automaticity 4) Conductivity

2) Contractility Cardiac cells have different properties that are associated with the stimulation and formation of impulse. The property of the cardiac cell to respond mechanically to an impulse is called contractility. The property of the cardiac cell to be electrically stimulated is called excitability. The property of the cardiac cell to initiate an impulse spontaneously and continuously is called automaticity. The property of the cardiac cell to transmit an impulse along a membrane in an orderly manner is called conductivity.

While explaining temporary pacemakers to a group of nursing students, what should the nurse include? Select all that apply. 1) All temporary pacemakers are transvenous. 2) Epicardial pacing involves attaching leads to the epicardium during heart surgery. 3) A transvenous pacemaker consists of leads that are threaded into the left ventricle. 4) Epicardial pacemakers are inserted in emergency departments and critical care units in emergency situations. 5) A transvenous pacemaker is attached to an external power source. 6) The placement of a transcutaneous pacemaker is noninvasive; it is a temporary procedure.

2) Epicardial pacing involves attaching leads to the epicardium during heart surgery. 5) A transvenous pacemaker is attached to an external power source. 6) The placement of a transcutaneous pacemaker is noninvasive; it is a temporary procedure. Epicardial pacing wires are inserted into the epicardial wall of the heart during cardiac surgery. The wires are brought through the chest wall and can be connected to a pulse generator if needed. Four wires are placed through the chest wall of the patient, two wires from the atrium and two wires from the ventricles. These four wires are connected to the temporary pacemaker, and pacing thresholds are set for each patient. With transvenous pacemakers, a pacing catheter is inserted percutaneously into the right ventricle, where it gets connected to the endocardium near the ventricular septum. It is connected to a small external pulse generator by electrode wires. Placement of the transcutaneous pacemaker is noninvasive and a temporary method until a more permanent treatment is sought. Transcutaneous pacemakers use electrical stimulation that is delivered through the skin via external electrode pads connected to an external pacemaker (a defibrillator with pacemaker functions). Temporary pacemakers include transcutaneous pacemakers, transvenous pacemakers, and epicardial pacemakers.

What should a nurse advise a group of caregivers with regards to a patient with an implantable cardioverter-defibrillator (ICD)? Select all that apply. 1) Restrict air travel 2) If the ICD fires more than once, contact the emergency response system (ERS) 3) Report any signs of infection at incision site 4) Restrict magnetic resonance imaging (MRI) scan 5) Restrict the lifting of the arm on the ICD site above the shoulder until approved

2) If the ICD fires more than once, contact the emergency response system (ERS) 3) Report any signs of infection at incision site 4) Restrict magnetic resonance imaging (MRI) scan 5) Restrict the lifting of the arm on the ICD site above the shoulder until approved The patient should be instructed to contact ERS if the ICD fires more than once. The patient with an ICD should immediately report any signs of infection such as redness, swelling, drainage, or fever. The patient should not undergo MRI scan unless the ICD is approved as MRI-safe. Also, the arm on the ICD side should not be lifted above the shoulder unless approved by the cardiologist. Air travel is not restricted. However, while traveling, the patient should inform the airport security personnel about the presence of ICD because it may set off the metal detector.

The nurse reviews a patient's admission history and identifies what findings that may be the cause of the patient's sinus bradycardia? Select all that apply. 1) Hyperthyroidism 2) Increased intracranial pressure 3) Hyperglycemia 4) Hypothermia 5) Calcium channel blockers

2) Increased intracranial pressure 4) Hypothermia 5) Calcium channel blockers The possible causes of sinus bradycardia include increased intracranial pressure, hypothermia, and treatment with calcium channel blockers. Increased intracranial pressure may suppress the cardiac centers in the brain, thus reducing the heart rate. Hypothermia may cause reduced venous return, thereby causing bradycardia. Calcium channel blockers cause bradycardia by decreasing automaticity of the SA node, and delaying the AV node conduction. The drug also reduces myocardial contractility. Hyperthyroidism increases the levels of thyroid hormone and increases the metabolism, resulting in tachycardia. Hyperglycemia causes tachycardia by causing systemic dehydration and acidosis.

The nurse reviews the following electrocardiogram (ECG) tracing. The nurse recognizes that the abnormal ECG finding is usually caused by what?? 1) Medications 2) Myocardial ischemia 3) Fluid overload 4) Dehydration

2) Myocardial ischemia Typical ECG changes that are seen in myocardial ischemia include ST segment depression and/or T wave inversion. Medications, fluid overload, and dehydration do not often affect the ST segment position on the ECG tracing.

An experienced nurse teaches a group of new graduate nurses about temporary pacemakers. What should the nurse include about indications for a temporary pacemaker? Select all that apply. 1) Heart failure 2) Prophylaxis after open heart surgery 3) Atrial fibrillation with slow ventricular response 4) Acute anterior myocardial infarction (MI) with second- or third-degree AV block 5) Acute inferior myocardial infarction (MI) with symptomatic bradycardia and AV block

2) Prophylaxis after open heart surgery 4) Acute anterior myocardial infarction (MI) with second- or third-degree AV block 5) Acute inferior myocardial infarction (MI) with symptomatic bradycardia and AV block A temporary pacemaker helps to maintain the normal pace of the heart when its electrical pathways are damaged. The power source of this device is placed outside the body. Temporary pacemakers are used after open heart surgery as prophylaxis. They are also indicated for use in patients with acute anterior MI with second- or third-degree heart block or bundle branch block. Indications also include for a patient with They are also indicated for patients with acute inferior myocardial infarction (MI) with symptomatic bradycardia and AV block. Heart failure and atrial fibrillation are not indications for a temporary pacemaker.

The nurse assesses a patient and notes a temperature of 101.6 F. Which type of dysrhythmia is associated with a fever? 1) Fibrillation 2) Sinus tachycardia 3) Sinus bradycardia 4) Junctional tachycardia

2) Sinus tachycardia A fever may cause tachycardia with a decrease in cardiac output and hypotension. Fibrillation can cause significant problems for a patient with complex disease processes, but it is not related to fever. Bradycardia and junctional tachycardia are not typical results of fever.

A patient's electrocardiogram (ECG) shows a heart rate of 150 beats/minute and a normal P wave preceding each QRS complex. How should the nurse interpret the finding? 1) Atrial fibrillation 2) Sinus tachycardia 3) Ventricular fibrillation 4) Premature atrial contractions

2) Sinus tachycardia Sinus tachycardia inhibits the vagus nerve or stimulates the sympathetic nervous system. This causes an increase in the heart rate to about 101 beats to 200 beats per minute. The electrocardiographic study of sinus tachycardia shows a normal P wave preceding each QRS complex with normal time and duration. In atrial fibrillation, the P waves are chaotic and fibrillary and the QRS complex is normal. The electrocardiographic study of ventricular fibrillation elicits the absence of P waves and the PR interval and QRS interval cannot be measured. In premature atrial contraction, there are distorted P waves in the ECG.

A patient's electrocardiogram (ECG) shows a heart rate of 150 beats/minute and a normal P wave preceding each QRS complex. How should the nurse interpret the finding? 1) Atrial fibrillation 2) Sinus tachycardia 3) Ventricular fibrillation 4) Premature atrial contractions

2) Sinus tachycardia Sinus tachycardia inhibits the vagus nerve or stimulates the sympathetic nervous system. This causes an increase in the heart rate to about 101 beats to 200 beats per minute. The electrocardiographic study of sinus tachycardia shows a normal P wave preceding each QRS complex with normal time and duration. In atrial fibrillation, the P waves are chaotic and fibrillatory and the QRS complex is normal. The electrocardiographic study of ventricular fibrillation elicits the absence of P waves and the PR interval and QRS interval cannot be measured. In premature atrial contraction, there are distorted P waves in the ECG.

The nurse is providing care for a patient with type I second-degree atrioventricular (AV) block. Which statements about this type of rhythm are true? Select all that apply. 1) A pacemaker is the only viable treatment. 2) Some P waves are conducted to the ventricles. 3) The P waves are not conducted to the ventricles. 4) If the patient is symptomatic, atropine or a pacemaker may be needed. 5) It may result from drugs such as digoxin. 6) It is generally transient and well tolerated

2) Some P waves are conducted to the ventricles. 4) If the patient is symptomatic, atropine or a pacemaker may be needed. 5) It may result from drugs such as digoxin. 6) It is generally transient and well tolerated Type I second-degree heart block refers to AV conduction that is intermittently blocked. Therefore, some P waves are conducted to the ventricle and some are not. Symptomatic patients may need atropine or a transcutaneous pacemaker. This type of heart block may result from drugs such as digoxin, and the condition is transient and well tolerated. If the patient is asymptomatic, no treatments may be needed. Third-degree block is often called complete heart block because no atrial impulses are conducted through the AV node to the ventricles.

A patient arrives in the emergency room with indigestion, shortness of breath, and back pain. The nurse reviews the results of the patient's 12-lead electrocardiogram (ECG) and notes ST elevation in leads II, III, and AVF. How should the nurse interpret the findings? 1) The patient has acute injury to the circumflex artery. 2) The patient has acute injury to the right coronary artery. 3) The patient has acute infarction of the left anterior descending artery. 4) The patient is not having a heart attack and most likely has gastric reflux.

2) The patient has acute injury to the right coronary artery. An ST elevation in leads II, III, and AVF indicates an acute injury to the inferior wall of the left ventricle involving the right coronary artery. An ST elevation in leads V1-V4 indicates acute infarction of the septal or anterior wall of the left ventricle involving the circumflex and left anterior descending arteries. An ST elevation with T wave inversion and a pathologic Q wave indicate acute infarction with cardiac cell death. A patient with symptoms of indigestion, shortness of breath, and back pains should have an immediate 12-lead ECG to rule out cardiac involvement; these symptoms indicate something more severe than reflux.

The nurse reviews a patient's electrocardiogram (ECG) and determines that the patient is experiencing type I second-degree atrioventricular (AV) block. The nurse made this interpretation based on what ECG characteristics? Select all that apply. 1) Every P wave is conducted to the ventricle. 2) Ventricular rate is slower. 3) Atrial rate is increased. 4) P wave is normal in shape. 5) PR intervals are consistent and greater than 0.20 second.

2) Ventricular rate is slower. 4) P wave is normal in shape. In type I second-degree AV block, AV conduction is intermittently blocked. Therefore, some P waves are conducted and some are not. Additionally, the ventricular rate may be slower. This is due to nonconducted or blocked QRS complexes and leads to bradycardia. The P wave has a normal shape. Atrial rate is normal. There is progressive lengthening of the PR intervals until another QRS complex is blocked.

When computing a heart rate on a patient's ECG tracing, the nurse counts 15 small blocks between an R-R interval. The rhythm is regular. What should the nurse document as the patient's heart rate? 1) 60 beats/minute 2) 75 beats/minute 3) 100 beats/minute 4) 150 beats/minute

3) 100 beats/minute Because each small block on the ECG paper represents 0.04 seconds, 1500 of these blocks represent one minute. By dividing the number of small blocks (15 in this case) into 1500, the nurse can calculate the heart rate in a patient whose rhythm is regular (in this case, 100). Sixty beats/minute, 75 beats/minute, and 150 beats/minute are incorrect answers.

The nurse that is monitoring the electrocardiogram (ECG) of a patient with hyperthyroidism observes regular, sawtooth-shaped flutter waves with an atrial rate 250 beats/minute. How should the nurse document this pattern? 1) Sinus bradycardia 2) Sinus tachycardia 3) Atrial flutter 4) Atrial fibrillation

3) Atrial flutter Atrial flutter is an atrial tachydysrhythmia identified by flutter (F) waves, a sawtoothed pattern, with a 200-350 beats/minute atrial rate. In sinus bradycardia, the heart rate is less than 60 beats/minute, with regular rhythm and normal P waves. Sinus tachycardia is identified by 101 to 200 beats/minute, with regular rhythm and normal P waves. In atrial fibrillation, atrial rate is 350 to 600 beats/minute, with irregular rhythm, and fibrillary (f) waves

A patient reports a sudden onset of dizziness. The nurse records the following electrocardiogram (ECG) tracing. The nurse suspects that the dizziness is most likely a result of what? 1) Inner ear infection 2) Myocardial infarction 3) Decreased cardiac output 4) Rapid metoprolol administration

3) Decreased cardiac output The patient's rhythm is paroxysmal supraventricular tachycardia (PSVT). Depending on the rate and duration of PSVT, the patient often experiences symptoms related to decreased cardiac output. The cardiac output drops because of decreased ventricular filling time. Although an inner ear infection can cause dizziness, the ECG tracing is more likely to be the source of the dizziness. The ECG tracing is not indicative of a myocardial infarction. Metoprolol is given to treat hypertension and to decrease the heart rate.

Which action does flecainide have on the heart? 1) Decreases automaticity 2) Accelerates depolarization 3) Decreases impulse conduction 4) Reduces myocardial contractility

3) Decreases impulse conduction Flecainide is a class IC sodium channel blocker; it decreases impulse conduction in patients. Mexiletine is a class IB sodium channel blocker that accelerates depolarization. B-adrenergic blockers like esmolol decrease the automaticity of the sinoatrial node. Myocardial contractility is reduced with diltiazem, a calcium channel blocker.

The nurse reviews a patient's electrocardiogram (ECG) tracing and notes a heart rate of 82 and an irregular rhythm. How should the nurse interpret the findings? 1) Sinus tachycardia 2) Junctional dysrhythmia 3) Premature atrial contractions 4) Paroxysmal supraventricular tachycardia

3) Premature atrial contractions When premature atrial contractions are present, the result is an irregular rhythm. In sinus tachycardia, the patient's heart rate is 101 to 200 beats per minute, and the cardiac rhythm is regular. A heart rate of 40 to 180 beats per minute with regular cardiac rhythm is observed in patients with junctional dysrhythmias. A heart rate of 150 to 220 beats per minute with regular cardiac rhythm is observed in patients with paroxysmal supra ventricular tachycardia.

The nurse reviews a patient's electrocardiogram (ECG) tracing and notes a heart rate of 82 and an irregular rhythm. How should the nurse interpret the findings? 1) Sinus tachycardia 2) Junctional dysrhythmia 3) Premature atrial contractions 4) Paroxysmal supraventricular tachycardia

3) Premature atrial contractions When premature atrial contractions are present, the result is an irregular rhythm. In sinus tachycardia, the patient's heart rate is 101 to 200 beats per minute, and the cardiac rhythm is regular. A heart rate of 40 to 180 beats per minute with regular cardiac rhythm is observed in patients with junctional dysrhythmias. A heart rate of 150 to 220 beats per minute with regular cardiac rhythm is observed in patients with paroxysmal supraventricular tachycardia.

The nurse is monitoring a patient on a wireless electrocardiogram (ECG) monitor. Which observation is a cause for concern? 1) Upright P wave 2) Flat ST segment 3) Prolonged QT interval 4) Upright T wave

3) Prolonged QT interval Prolonged QT interval is a cause for concern. QT disturbance may be caused by drugs, electrolyte imbalances, and changes in heart rate. Upright P wave, flat ST segment, and upright T wave are normal findings.

Which ECG characteristic is consistent with a diagnosis of ventricular tachycardia (VT)? 1) Unmeasurable rate and rhythm 2) Rate 150 beats/minute; inverted P wave 3) Rate 200 beats/minute; P wave not visible 4) Rate 125 beats/minute; normal QRS complex

3) Rate 200 beats/minute; P wave not visible VT is associated with a rate of 150 to 250 beats/minute; the P wave normally is not visible. Rate and rhythm are not measurable in ventricular fibrillation. P wave inversion and a normal QRS complex are not associated with VT.

The nurse suspects that a patient is experiencing myocardial infarction (MI). Which component of the patient's electrocardiogram (ECG) is most important for the nurse to analyze to make this determination? 1) P wave 2) PR interval 3) ST segment 4) Heart rate

3) ST segment The typical ECG change seen during myocardial injury is ST segment elevation. The P wave represents time for the passage of the electrical impulse through the atrium; there are no specific changes that occur with MI. A prolonged PR interval is indicative of a heart block and is usually not associated with MI. A specific change is heart rate is not associated with MI.

Which statement describes the electrical activity of the heart represented by the PR interval on an electrocardiogram (ECG)? 1) The length of time it takes to depolarize the atrium 2) The length of time it takes for the atria to depolarize and depolarize 3) The length of time for the electrical impulse to travel from the sinoatrial (SA) node to the Purkinje fibers 4) The length of time it takes for the electrical impulse to travel from the SA node to the atrioventricular (AV) node

3) The length of time for the electrical impulse to travel from the sinoatrial (SA) node to the Purkinje fibers The electrical impulse in the heart must travel from the SA node through the AV node and into the Purkinje fibers for synchronous atrial and ventricular contraction to occur. When measuring the PR interval (the time from the beginning of the P wave to the beginning of the QRS), the nurse is identifying the length of time it takes for the electrical impulse to travel from the SA node to the Purkinje fibers. The P wave represents the length of time it takes for the impulse to travel from the SA node through the atrium, causing depolarization of the atria (atrial contraction). Atrial repolarization occurs during ventricular depolarization and is hidden by the QRS complex. The length of time it takes for the electrical impulse to travel from the SA node to the AV node is the flat line between the end of the P wave and the beginning of the Q wave on the ECG and usually is not measured.

A patient's electrocardiogram (ECG) tracing has changed from sinus tachycardia (ST) to the following rhythm. What should the nurse conclude from the ECG finding? 1) The patient is at risk for a pulmonary embolism 2) The patient is at risk for ventricular tachycardia 3) The patient is experiencing a myocardial infarction 4) The patient is showing signs of an elevated potassium level

3) The patient is experiencing a myocardial infarction ST elevation is a manifestation of a myocardial infarction (MI). ST elevation does not increase a patient's risk of a pulmonary embolism. A patient can go into ventricular tachycardia because of an MI, but it is not the main reason the nurse would notify the primary health care provider in this situation. Hyperkalemia is evidenced by a peaked T wave, not ST elevation.

Which type of arrhythmia is associated with the absence of P waves on an electrocardiogram (ECG)? 1) Sinus tachycardia 2) Sinus bradycardia 3) Ventricular fibrillation 4) Type II second-degree AV block

3) Ventricular fibrillation Ventricular fibrillation is associated with the absence of P waves on an electrocardiogram (ECG) because of a decrease in cardiac output. P waves are visible with sinus tachycardia, sinus bradycardia, and type II second-degree AV block rhythms.

The nurse expects to assess what heart rate in a patient with paroxysmal supraventricular tachycardia (PSVT)? 1) Slower than 60 beats/minute 2) Between 60 and 100 beats/minute 3) Between 100 and 150 beats/minute 4) Between 150 and 220 beats/minute

4) Between 150 and 220 beats/minute Paroxysmal supraventricular tachycardia (PSVT) is characterized by a heart rate of 150 to 220 beats/minute. A heart rate of fewer than 60 beats/minute is considered bradycardia. A rate of 100 beats/minute is the upper limit for a normal heart rate, and a rate of 100 to 150 beats/minute is the range for a sinus tachycardia.

The nurse notes artifact on a patient's telemetry monitor. Which factors contribute to artifact? 1) Disabled automaticity 2) Stimulation of the vagus nerve fibers 3) Electrodes placed in the incorrect lead 4) Excessive hair under the electrode pads

4) Excessive hair under the electrode pads One reason that artifact is seen on the monitor is when leads and electrodes are not secure. Electrode pads may not be secure if there is excessive hair under the pads, the skin is oily, or if diaphoresis is present. Disabled automaticity would cause an atrial dysrhythmia. Electrodes placed in the incorrect place will measure electricity in a different plane of the heart and may have a different wave form than expected. Stimulation of the vagus nerve fibers causes a decrease in heart rate, not artifact.

What is a disadvantage of a centralized monitoring system? 1) It cannot diagnose dysrhythmias 2) It measures the patients' heart rate remotely 3) It cannot rapidly detect myocardial ischemia 4) It requires continuous observation of patients' ECGs

4) It requires continuous observation of patients' ECGs A centralized monitoring system is a type of telemetry monitoring system. It requires continuous observation of a group of patients' electrocardiograms at a central location. Centralized monitoring systems observe heart rate and rhythm remotely, at a site distant from the patient. A centralized monitoring system helps to detect dysrhythmias, ischemia, or infarction in patients.

A patient with paroxysmal supraventricular tachycardia (PSVT) that is receiving intravenous adenosine becomes hemodynamically unstable. The nurse expects what to be included in the patient's immediate treatment plan? 1) β-adrenergic blocker 2) Calcium channel blocker 3) Catheter ablation therapy 4) Synchronized cardioversion

4) Synchronized cardioversion Paroxysmal supraventricular tachycardia is a dysrhythmia starting in an ectopic focus anywhere above the bifurcation of the bundle of His. The standard drug of choice to treat paroxysmal supraventricular tachycardia is intravenous (IV) adenosine. Sometimes the drug therapy is ineffective and the patient becomes hemodynamically unstable. For patients who are unresponsive to treatment, synchronized cardioversion is used. Synchronized cardioversion is low energy shock, which uses a sensor to deliver electricity that is synchronized with the peak of the QRS complex. Drug therapy is not effective for such patients. β -adrenergic blockers and calcium channel blockers do not improve paroxysmal supraventricular tachycardia. Catheter ablation therapy is used in patients with Wolff-Parkinson-White syndrome who have recurring paroxysmal supraventricular tachycardia (PSVT).

The nurse reviews the electrocardiogram (ECG) tracing of a patient with an electrolyte imbalance and expects to find a disturbance in which waveform? 1) P wave 2) Q wave 3) S wave 4) T wave

4) T wave The T wave represents ventricular repolarization in an electrocardiogram. Disturbances (e.g., tall, peaked, inverted) in T waves can occur due to electrolyte imbalances, ischemia, and infarction. Disturbances in the P wave can be due to alterations in atrial conduction. Disturbances in the Q wave can occur due to myocardial infraction. Disturbances in the S wave do not affect the normal functioning of heart.

The nurse understands that a pacemaker is used for which type of dysrhythmia? 1) Atrial fibrillation 2) Ventricular fibrillation 3) Ventricular tachycardia 4) Third-degree AV block

4) Third-degree AV block The use of a pacemaker (temporary or permanent) is considered a lifesaving measure for patients who have experienced heart block, particularly third-degree or complete heart block. A temporary pacemaker may be used until the block is resolved through medical interventions or a permanent pacemaker is inserted. In special situations, a pacemaker may be used for ventricular fibrillation or ventricular tachycardia; however, this is more an exception rather than routine. Atrial fibrillation is treated with medication such as diltiazem or synchronized electrical cardioversion. In special situations a ventricular pacemaker may be used for ventricular fibrillation or ventricular tachycardia; however, this is more an exception rather than routine.

The nurse recognizes that which cardiac dysrhythmia is life-threatening and necessitates immediate intervention? 1) Sinus tachycardia 2) Atrial fibrillation 3) Junctional tachycardia 4) Ventricular fibrillation

4) Ventricular fibrillation Ventricular fibrillation is a life-threatening dysrhythmia that requires immediate intervention. During ventricular fibrillation, the ventricles are quivering and are no longer able to contract to produce effective cardiac output. Because there is no cardiac output, the body is left without oxygenation. Sinus tachycardia requires treatment to slow the rate to 60 to 100 beats/minute. Atrial fibrillation requires treatment to convert the rhythm back to a normal sinus rhythm with one atrial contraction for every ventricular contraction. Normal sinus rhythm, in which the rate is 60 to 100 beats/minute, requires no treatment.

A patient is diagnosed with pulseless ventricular tachycardia. The nurse should perform the steps of defibrillation in what order?

Defibrillation is the treatment of choice for pulseless ventricular tachycardia. The nurse should first turn the defibrillator on and select the proper energy level, then check to see that the synchronizer switch is turned off. The nurse then should apply conductive materials to the chest and charge the defibrillator using the button on the defibrillator or the paddles. The nurse should then position the paddles firmly on the chest wall over the conductive material. Finally, the nurse should deliver the charge by depressing buttons on both paddles simultaneously.

The nurse provides teaching about the conduction system of the heart to a group of nursing students. The nurse should include that the electrical impulses travel through the heart in what order? 1) Bundle of His 2) Sinoatrial node 3) Purkinje fibers 4) Internodal pathways 5) Atrioventricular node

Sinoatrial node Internodal pathways Atrioventricular node Bundle of His Purkinje fibers The conduction system of the heart consists of specialized neuromuscular tissue. The electrical impulse of the heart begins at the sinoatrial node in the upper right atrium. This impulse travels through the intermodal fibers and spreads over the atrial musculature. This causes atrial contraction. The impulse then reaches the atrioventricular (AV) node. From the AV node the impulse moves down through the bundle of His and ends at the Purkinje fibers. Impulses from the Purkinje fibers cause ventricular contractions.

The nurse reviews the cardiac cycle and ectopic impulses. The nurse identifies that the greatest risk to the patient is when the ectopy occurs in which part of the cycle?

The patient is at greatest risk if the ectopic impulse falls on the T wave of a preceding beat. This is called the R-on-T phenomenon. This is especially dangerous because the PVC is firing during the relative refractory period of ventricular repolarization. Excitability of the heart cells increases during this time, and the risk for the PVC to start VT or ventricular fibrillation (VF) is great.