CARDIAC DYSRHYTHMIAS - S1

Frequent premature ventricular contractions (PVCs) (>1 every 10 beats) may reduce the cardiac output and precipitate angina and ____________, depending on their frequency. Because PVCs in CAD or acute myocardial infarction indicate ventricular irritability, the patient's physiologic response to PVCs must be monitored. Frequent PVCs most likely must be treated with oxygen therapy, electrolyte replacement, or antidysrhythmic agents.

HF

The nurse observes a prominent U wave on the client's ECG tracing. What is the nurse's interpretation of this finding? This is a normal finding. The client may have a potassium imbalance. The client is at risk for R-on-T phenomenon. The client has an evolving myocardial infarction.

The client may have a potassium imbalance.

Cardioversion is attempted for a patient with atrial flutter and a rapid ventricular response. After the delivering 50 joules by synchronized cardioversion, the patient develops ventricular fibrillation. Which action should the nurse take immediately? Administer 250 mL of 0.9% saline solution IV by rapid bolus. Turn the synchronizer switch to the "off" position and recharge the device. Assess the apical pulse, blood pressure, and bilateral neck vein distention. Tell the patient to report any chest pain or discomfort and administer morphine sulfate.

(CORRECT) Turn the synchronizer switch to the "off" position and recharge the device. - Ventricular fibrillation produces no effective cardiac contractions or cardiac output. If during synchronized cardioversion the patient becomes pulseless or the rhythm deteriorates to ventricular fibrillation, the nurse should turn the synchronizer switch off and initiate defibrillation. Fluids, additional assessment, or treatment of pain alone will not restore an effective heart rhythm.

A client's ECG tracing shows a run of sustained ventricular tachycardia. What is the first action that the nurse will take? Assess the client's airway, breathing, and level of consciousness. Administer verapamil IV push. Defibrillate the client. Begin cardiopulmonary resuscitation (CPR).

Assess the client's airway, breathing, and level of consciousness.

Which of the following conditions are not thought to cause atrial fibrillation? A. Mitral stenosis B. Mitral regurgitation C. Tricuspid regurgitation D. Peripheral vascular disease

D. Peripheral vascular disease

A client with third-degree AV block presents to the emergency room with a heart rate of 40 beats/min. Which nursing diagnosis would most likely be a priority for this client? Increased Cardiac Output Decreased Cardiac Output Impaired Electrical Conduction Impaired Self-Care Management

Decreased Cardiac Output

What does the P wave on an ECG tracing represent? Contraction of the atria Contraction of the ventricles Depolarization of the atria Depolarization of the ventricles

Depolarization of the atria

Atrial fibrillation is characterized by random p-waves on the EKG. True False

False

The R waves in atrial fibrillation are regular. True False

False

Select a MOA for the following medications: Medication: diltiazem (Cardizem) Medication: verapamil (Calan) Mechanism of action: decreases automaticity of the SA node, slows impulse conduction in AV node, reduces atrial and ventricular contractility Mechanism of action: Delays repolarization, prolonging duration of action potential and refractory period Mechanism of action: Decreases automaticity of SA node, delays atrioventricular (AV) node conduction; reduces myocardial Dilates coronary arteries, peripheral arterioles, and arteries, and slows cardiac contractility

Mechanism of action: Decreases automaticity of SA node, delays atrioventricular (AV) node conduction; reduces myocardial Dilates coronary arteries, peripheral arterioles, and arteries, and slows cardiac contractility

Select a MOA for the following medications: Medication: amiodarone (Pacerone) Medication: ibutilide (Corvert) Medication: dofetilide (Tikosyn) Mechanism of action: decreases automaticity of the SA node, slows impulse conduction in AV node, reduces atrial and ventricular contractility Mechanism of action: Delays repolarization, prolonging duration of action potential and refractory period Mechanism of action: Decreases automaticity of SA node, delays atrioventricular (AV) node conduction; reduces myocardial Dilates coronary arteries, peripheral arterioles, and arteries, and slows cardiac contractility

Mechanism of action: Delays repolarization, prolonging duration of action potential and refractory period

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

P wave

Which action will the nurse take to improve the quality of the electrocardiographic rhythm transmission to the monitoring system? Apply lotion to the client's chest before attaching the chest leads. Remove the hair from the chest area before attaching the chest leads. Instruct the client not to wear any clothing made from synthetic fabrics during the test. Apply skin protectant to area prior to placing electrode.

Remove the hair from the chest area before attaching the chest leads.

P-waves are absent in atrial flutter. True False

True

The hallmark of atrial flutter are "saw-tooth" waves, sometimes called F-waves. True False

True

Which dysrhythmia may develop in a client with frequent premature ventricular contractions? Sinus tachycardia Rapid atrial flutter Ventricular tachycardia Atrioventricular junctional rhythm

Ventricular tachycardia

cardioversion indication

Vtach

ICD indications

implanted cardiac defibrillator- prevents sudden cardiac death in patients >40 days post MI, EF <35% class II or III symptoms despite medical tx

Repolarization =

relaxation

A T wave follows the QRS complex and indicates ventricular _____________.

repolarization

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

(CORRECT) 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 in order 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 is not usually measured.

The client with tachycardia is experiencing clinical manifestations. Which one alerts the nurse to the need for immediate intervention? Chest pain Increased urine output Mild orthostatic hypotension P wave touching the T wave

Chest pain

A client is experiencing sinus bradycardia with hypotension and dizziness. What medication does the nurse administer? a. Atropine (Atropine) b. Digoxin (Lanoxin) c. Lidocaine (Xylocaine) d. Metoprolol (Lopressor)

a. Atropine (Atropine) - Atropine is a cholinergic antagonist that inhibits parasympathetically-induced hyperpolarization of the sinoatrial node. This inhibition results in an increased heart rate. The other medications are not appropriate.

A nurse is caring for a client with chronic atrial fibrillation who is at risk for systemic emboli. Which drug should the nurse expect to administer to prevent this complication? Sotalol (Betapace) Heparin (Heparin) Atropine (Atropine) Lidocaine (Xylocaine)

Heparin (Heparin)

The client is experiencing occasional premature atrial contractions (PACs) accompanied by palpitations. These episodes resolve spontaneously without treatment. What instructions will be included in a teaching plan for this client? Limit or abstain from caffeine. Lie on your left side until the attack subsides. Use your oxygen whenever you experience PACs. Take your quinidine twice daily on the days that you experience palpitations.

Limit or abstain from caffeine.

Select a MOA for the following medications: Medication: atenolol (Tenormin) Medication: metoprolol (Lopressor) Mechanism of action: decreases automaticity of the SA node, slows impulse conduction in AV node, reduces atrial and ventricular contractility Mechanism of action: Delays repolarization, prolonging duration of action potential and refractory period Mechanism of action: Decreases automaticity of SA node, delays atrioventricular (AV) node conduction; reduces myocardial Dilates coronary arteries, peripheral arterioles, and arteries, and slows cardiac contractility

Mechanism of action: decreases automaticity of the SA node, slows impulse conduction in AV node, reduces atrial and ventricular contractility

The nurse prepares to defibrillate a patient. For which dysrhythmia has the nurse observed in this patient? Uncontrolled atrial fibrillation Ventricular fibrillation Ventricular tachycardia with a pulse Third-degree AV block

Uncontrolled atrial fibrillation (CORRECT) Ventricular fibrillation - Defibrillation is always indicated in the treatment of ventricular fibrillation. Drug treatments are normally 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). Pacemakers are the treatment of choice for third-degree heart block. Ventricular tachycardia with a pulse Third-degree AV block

A client has a heart rate averaging 56 beats/min with no adverse symptoms. What activity modifications does the nurse suggest to avoid further slowing of the heart rate? a. "Make certain that your bath water is warm (100° F)." b. "Avoid bearing down or straining while having a bowel movement." c. "Avoid strenuous exercise, such as running, during the late afternoon." d. "Limit your intake of caffeinated drinks to no more than 2 cups per day."

b. "Avoid bearing down or straining while having a bowel movement." - Bearing down strenuously during a bowel movement is one type of Valsalva maneuver, which stimulates the vagus nerve and results in slowing of the heart rate. Such a response is not desirable in a person who has bradycardia. The other instructions are not appropriate for this condition.

A client with myocardial ischemia is having frequent early, wide ventricular complexes seen on the cardiac monitor. Which medication does the nurse administer? a. Lanoxin (Digoxin) b. Amiodarone (Cordarone) c. Dobutamine (Dobutamine) d. Atropine sulfate (Atropisol)

b. Amiodarone (Cordarone) - Early, wide ventricular complexes are premature ventricular contractions (PVCs). Amiodarone, an antidysrhythmic, is the treatment of choice for frequent PVCs. The other medications are not appropriate for this condition.

The nurse is caring for a client with a temporary pacemaker. The client's bedside monitor shows a spike followed by a QRS complex. What is the nurse's best action? a. Remove the pacemaker; it is not needed. b. Decrease the threshold of the pacemaker. c. Document the finding in the client's chart. d. Set the pacemaker to the synchronous mode.

c. Document the finding in the client's chart. - A spike followed by a QRS complex indicates "capture," meaning that the pacemaker has successfully depolarized or captured the ventricle. No action other than documentation of this finding is necessary.

The nurse is assessing clients at a community clinic. Which client does the nurse assess most carefully for atrial fibrillation? a. Middle-aged client who takes an aspirin daily b. Client who is dismissed after coronary artery bypass surgery c. Older adult client after a carotid endarterectomy d. Client with chronic obstructive pulmonary disease

b. Client who is dismissed after coronary artery bypass surgery - Atrial fibrillation occurs commonly in clients with cardiac disease and is a common occurrence after coronary artery bypass graft (CABG) surgery. The other conditions do not place a client at higher risk for atrial fibrillation.

A client with ventricular tachycardia (VT) is unresponsive and has no pulse. The nurse calls for assistance and a defibrillator. What is the nurse's priority intervention while waiting for the defibrillator to arrive?a. Perform a pericardial thump. b. Initiate cardiopulmonary resuscitation. c. Start an 18-gauge IV in the antecubital. d. Ask the client's family about code status.

b. Initiate cardiopulmonary resuscitation. - A client with pulseless VT should be defibrillated immediately. If the defibrillator is not available, the nurse should initiate cardiopulmonary resuscitation (CPR) and then should defibrillate as soon as possible. Basic life support (BLS) is the basis of emergency cardiac care; if the client does not have an IV already, this can wait until others have arrived to help. Providing good quality CPR is vital. The client should have already been assessed for code status.

A client with unstable ventricular tachycardia is receiving amiodarone by intravenous infusion. The nurse notes that the client's heart rate has decreased from 68 to 50 beats/min. The client is asymptomatic. What is the nurse's priority intervention? a. Stop the infusion and flush the IV. b. Slow the amiodarone infusion rate. c. Administer a precordial thump. d. Place the client in a side-lying position.

b. Slow the amiodarone infusion rate. -IV administration of amiodarone may cause bradycardia and atrioventricular (AV) block. The correct action for the nurse to take at this time is to slow the infusion, because the client is asymptomatic and no evidence reveals AV block that might require pacing. Abruptly ceasing the medication could allow fatal dysrhythmias to occur. A precordial thump is not required at this time because the client still has a heart rate. A side-lying position will not increase the client's heart rate.

The nurse is caring for a client with atrial fibrillation. What manifestation most alerts the nurse to the possibility of a serious complication from this condition? a. Sinus tachycardia b. Speech alterations c. Fatigue d. Dyspnea with activity

b. Speech alterations - Clients with atrial fibrillation are at risk for embolic stroke. Evidence of embolic events includes changes in mentation, speech, sensory function, and motor function. Clients with atrial fibrillation often have a rapid ventricular response as a result. Fatigue is a nonspecific complaint. Clients with atrial fibrillation often have dyspnea as a result of the decreased cardiac output caused by the rhythm disturbance.

The nurse has administered adenosine (Adenocard). What is the expected therapeutic response? a. Increased intraocular pressure b. A brief tonic-clonic seizure c. A short period of asystole d. Hypertensive crisis

c. A short period of asystole - Clients usually respond to this medication with a short period of asystole, bradycardia, hypotension, dyspnea, and chest pain.

The nurse is caring for a client with a complete heart block (third-degree atrioventricular [AV] block). What is the nurse's priority intervention? a. Perform a cardioversion. b. Assist with carotid massage. c. Begin external pacing. d. Administer adenosine (Adenocard) IV.

c. Begin external pacing. - The nurse would expect the client with complete heart block or third-degree AV block to be paced externally until the client can be scheduled for a permanent pacemaker.

The client's heart rate increases slightly during inspiration and decreases slightly during expiration. What action does the nurse take? a. Evaluate for a respirator disorder. b. Assess the client for chest pain. c. Document the finding in the chart. d. Administer antidysrhythmic drugs.

c. Document the finding in the chart. - Sinus dysrhythmia is noted when the heart rate increases slightly during inspiration and decreases slightly during expiration. Sinus dysrhythmia is a variant of normal sinus rhythm that is frequently observed in healthy children and adults. No other actions are needed.

A client with third-degree heart block is admitted to the telemetry unit. The nurse observes wide QRS complexes on the monitor with a heart rate of 35 beats/min. What priority assessment does the nurse perform? a. Pulmonary auscultation b. Pulse strength and amplitude c. Level of consciousness d. Mobility and gait stability

c. Level of consciousness - A heart rate of 40 beats/min or less, with widened QRS complexes, could have hemodynamic consequences, and the client is at risk for inadequate cerebral perfusion. The nurse should assess for level of consciousness, lightheadedness, confusion, syncope, and seizure activity.

The nurse identifies a client's rhythm to be a sustained supraventricular tachycardia. What medication does the nurse administer? a. Atropine (Atropine) b. Epinephrine (Adrenalin) c. Lidocaine (Xylocaine) d. Diltiazem (Cardizem)

d. Diltiazem (Cardizem) - Diltiazem, a calcium channel blocker, slows depolarization through the conduction system and is commonly used as an agent to terminate a sustained episode of supraventricular tachycardia.

The nurse is caring for a client on a cardiac monitor. The monitor shows a rapid rhythm with a "saw tooth" configuration. What physical assessment findings does the nurse expect? a. Presence of a split S1 and wheezing b. Anorexia and gastric distress c. Shortness of breath and anxiety d. Hypertension and mental status change

c. Shortness of breath and anxiety - The rhythm described is atrial flutter with a rapid ventricular response. Rapid atrial flutter may manifest with palpitations, shortness of breath, and anxiety. Syncope, angina, and evidence of heart failure also may be present

Depolarization =

contraction

A cardiac catheterization enables visualization of _____________ and is thus useful in diagnosing CAD

coronary arteries

The nurse is recovering a client after insertion of an implantable cardioverter-defibrillator (ICD). What complication must the nurse intervene for immediately? a. 2/4 bilateral peripheral edema b. Heart rate of 56 beats/min c. Temperature of 96° F (35.5° C) d. Muffled heart sounds

d. Muffled heart sounds - In the postimplantation period, the nurse should be alert for complications of cardiac tamponade, bleeding, and dysrhythmias. Muffled heart sounds are a manifestation of cardiac tamponade. Edema and a lower temperature would not be indicative of a complication of this procedure. Bradycardia might need intervention, but this client's heart rate is not critically low.

When analyzing a client's electrocardiograph (ECG) tracing, the nurse observes that not all QRS complexes are preceded by a P wave. What is the nurse's interpretation of this observation? a. The client has hyperkalemia causing irregular QRS complexes. b. Ventricular tachycardia is overriding the normal atrial rhythm. c. The client's chest leads are not making sufficient contact with the skin. d. Ventricular and atrial depolarizations are initiated from different sites.

d. Ventricular and atrial depolarizations are initiated from different sites. - Normal rhythm shows one P wave preceding each QRS, indicating that all depolarization is initiated at the sinoatrial node. QRS complexes without a P wave indicate a different source of initiation of depolarization.

An echocardiogram uses ultrasound to assess heart structure and movements and is thus useful in diagnosing ________ disorders.

valvular

Defibrillation is always indicated in the treatment of ventricular fibrillation. Drug treatments are normally used in the treatment of uncontrolled atrial fibrillation and for ventricular tachycardia ______________ (if the patient is stable).

with a pulse