NCLEX Dysrhythmias & EKG Interpretation Practice Exam Quiz
Which of the following EKG findings is characteristic of atrial fibrillation?
A) Wide QRS complex
B) Irregularly irregular rhythm
C) P waves are visible
D) QRS complexes are absent
What is the hallmark of ventricular tachycardia on an EKG?
A) P wave before each QRS
B) Fast, wide QRS complexes
C) Shortened PR interval
D) Absence of QRS complexes
Which of the following is a sign of a third-degree AV block?
A) Prolonged PR interval
B) Regular P to QRS ratio
C) No relation between P waves and QRS complexes
D) T wave inversion
What is the first-line treatment for atrial fibrillation with rapid ventricular response?
A) Beta-blockers
B) Anticoagulants
C) Defibrillation
D) Amiodarone
Which of the following is characteristic of a normal sinus rhythm?
A) Heart rate 100-150 bpm
B) Regular rhythm, P wave before each QRS
C) P wave absent
D) QRS complexes greater than 0.12 seconds
In an EKG, what does the QRS complex represent?
A) Atrial depolarization
B) Ventricular depolarization
C) Atrial repolarization
D) Ventricular repolarization
What is the characteristic EKG finding in hyperkalemia?
A) Tall, peaked T waves
B) Prolonged QT interval
C) Shortened PR interval
D) Small P waves
Which of the following is the most appropriate treatment for ventricular fibrillation?
A) Administer atropine
B) Cardioversion
C) Defibrillation
D) Lidocaine infusion
What does a prolonged QT interval increase the risk of?
A) Bradycardia
B) Tachycardia
C) Torsades de pointes
D) Atrial fibrillation
Which of the following is the most common cause of sinus bradycardia?
A) Vagal stimulation
B) Hyperthyroidism
C) Drug overdose
D) Increased sympathetic stimulation
A prolonged PR interval on an EKG indicates which type of heart block?
A) First-degree AV block
B) Second-degree AV block Type I
C) Second-degree AV block Type II
D) Third-degree AV block
In an EKG strip, what does the T wave represent?
A) Ventricular depolarization
B) Atrial depolarization
C) Ventricular repolarization
D) Atrial repolarization
What is the primary treatment for supraventricular tachycardia (SVT)?
A) Cardioversion
B) Vagal maneuvers
C) Epinephrine administration
D) Defibrillation
What is the primary concern when assessing a patient with a third-degree heart block?
A) Low blood pressure
B) Bradycardia and reduced cardiac output
C) Tachycardia
D) Elevated heart rate
What is the classic appearance of “sawtooth” waves in an EKG?
A) Atrial flutter
B) Atrial fibrillation
C) Ventricular fibrillation
D) Sinus tachycardia
Which EKG finding is indicative of a myocardial infarction?
A) ST segment depression
B) Shortened PR interval
C) ST segment elevation
D) Inverted P waves
What does the U wave typically represent in an EKG?
A) Ventricular depolarization
B) Atrial depolarization
C) Repolarization of the Purkinje fibers
D) Ventricular repolarization
What is the primary treatment for atrial fibrillation with rapid ventricular response?
A) Digoxin
B) Anticoagulants
C) Beta-blockers or calcium channel blockers
D) Amiodarone
What does a P wave represent on an EKG?
A) Atrial depolarization
B) Ventricular depolarization
C) Ventricular repolarization
D) Atrial repolarization
Which EKG rhythm is characterized by an absent P wave and a wide QRS complex?
A) Atrial fibrillation
B) Premature ventricular complex
C) Ventricular tachycardia
D) Junctional rhythm
Which of the following is a risk factor for developing atrial fibrillation?
A) Hyperthyroidism
B) Hypertension
C) Coronary artery disease
D) All of the above
What is the purpose of administering atropine in the case of bradycardia?
A) Increase heart rate
B) Lower blood pressure
C) Slow down conduction
D) Decrease heart rate
What is the primary intervention for patients with symptomatic bradycardia?
A) Amiodarone administration
B) IV fluids
C) Atropine administration
D) External defibrillation
What is the effect of digitalis toxicity on the heart rhythm?
A) Sinus tachycardia
B) Sinus bradycardia and AV block
C) Ventricular fibrillation
D) Atrial fibrillation
Which of the following is an indication for synchronized cardioversion?
A) Ventricular fibrillation
B) Atrial fibrillation
C) Asystole
D) Pulseless electrical activity
What does a prolonged QT interval indicate?
A) Increased risk of sudden death from arrhythmia
B) Increased risk of stroke
C) Increased heart rate
D) Decreased risk of arrhythmias
Which EKG rhythm is characterized by a “regularly irregular” pattern?
A) Atrial fibrillation
B) Ventricular tachycardia
C) Premature atrial contractions
D) Sinus arrhythmia
What is a common cause of a U wave in an EKG?
A) Hyperkalemia
B) Hypokalemia
C) Hypercalcemia
D) Hypocalcemia
What is the primary cause of a myocardial infarction-related arrhythmia?
A) Tissue ischemia
B) Increased sympathetic tone
C) Decreased parasympathetic tone
D) Hypoxia
Which of the following is a classic symptom of a PVC (Premature Ventricular Contraction)?
A) Skipped heartbeat
B) Increased heart rate
C) Chest pain
D) Low blood pressure
Which rhythm is characterized by a progressive lengthening of the PR interval until a beat is dropped?
A) First-degree AV block
B) Second-degree AV block Type I (Wenckebach)
C) Second-degree AV block Type II
D) Third-degree AV block
Which rhythm requires immediate defibrillation?
A) Atrial flutter
B) Ventricular fibrillation
C) Sinus tachycardia
D) Atrial fibrillation
What is the defining feature of a junctional rhythm?
A) Absent QRS complex
B) No visible P wave or inverted P wave
C) Narrow QRS complex with a normal P wave
D) Wide QRS complex
In a patient with atrial flutter, the atrial rate is typically:
A) 60-100 bpm
B) 100-250 bpm
C) 250-350 bpm
D) 350-500 bpm
Which medication is used to terminate paroxysmal supraventricular tachycardia (PSVT)?
A) Atropine
B) Adenosine
C) Amiodarone
D) Epinephrine
What is the distinguishing characteristic of a left bundle branch block (LBBB) on an EKG?
A) Wide QRS complexes with a “bunny ear” pattern in leads V5 and V6
B) Narrow QRS complexes
C) ST segment depression
D) T wave inversion
Which EKG change indicates ischemia?
A) ST segment elevation
B) ST segment depression
C) Prolonged PR interval
D) Widened QRS complex
Which rhythm is treated with atropine for bradycardia?
A) Sinus bradycardia
B) Ventricular tachycardia
C) Ventricular fibrillation
D) Junctional tachycardia
What is the rate for a ventricular escape rhythm?
A) 40-60 bpm
B) 60-100 bpm
C) 20-40 bpm
D) 100-150 bpm
Which rhythm is most commonly associated with sudden cardiac arrest?
A) Atrial flutter
B) Ventricular tachycardia
C) Ventricular fibrillation
D) Junctional rhythm
What is the most appropriate intervention for asystole?
A) Immediate defibrillation
B) Chest compressions and epinephrine
C) Synchronized cardioversion
D) Administer atropine
What is the normal duration of a QRS complex?
A) 0.06-0.10 seconds
B) 0.12-0.20 seconds
C) 0.20-0.30 seconds
D) 0.30-0.40 seconds
What medication is given for Torsades de Pointes?
A) Magnesium sulfate
B) Atropine
C) Adenosine
D) Digoxin
What defines pulseless electrical activity (PEA)?
A) No electrical activity on EKG
B) Electrical activity with no palpable pulse
C) Irregular rhythm
D) Wide QRS complexes
Which electrolyte imbalance is associated with U waves on an EKG?
A) Hypokalemia
B) Hyperkalemia
C) Hypocalcemia
D) Hypercalcemia
What is the purpose of synchronized cardioversion?
A) To treat pulseless electrical activity
B) To reset the heart rhythm in a controlled manner
C) To defibrillate the heart
D) To increase the heart rate
What does an inverted T wave indicate?
A) Myocardial ischemia
B) Hyperkalemia
C) Ventricular fibrillation
D) Junctional rhythm
Which rhythm has no identifiable P waves, a narrow QRS complex, and a rate of 150-250 bpm?
A) Atrial fibrillation
B) Junctional tachycardia
C) Supraventricular tachycardia (SVT)
D) Ventricular tachycardia
What does an elevated ST segment suggest?
A) Myocardial infarction
B) Hypokalemia
C) Ventricular fibrillation
D) First-degree AV block
Which rhythm is associated with wide QRS complexes and a rate above 100 bpm?
A) Atrial flutter
B) Ventricular tachycardia
C) Sinus tachycardia
D) Atrial fibrillation
What is a key feature of second-degree AV block Type II?
A) Gradual lengthening of PR interval
B) Dropped QRS without PR lengthening
C) Narrow QRS complexes
D) Accelerated heart rate
Which rhythm is treated with a pacemaker?
A) Ventricular fibrillation
B) Third-degree heart block
C) Atrial fibrillation
D) Sinus tachycardia
What does a delta wave in the QRS complex suggest?
A) Wolf-Parkinson-White Syndrome
B) Ventricular fibrillation
C) Hyperkalemia
D) Atrial fibrillation
What is the normal PR interval duration?
A) 0.04-0.08 seconds
B) 0.08-0.12 seconds
C) 0.12-0.20 seconds
D) 0.20-0.24 seconds
What does a prominent Q wave suggest?
A) Past myocardial infarction
B) Ventricular fibrillation
C) Hypercalcemia
D) Tachycardia
What is the primary treatment for unstable atrial fibrillation with a rapid ventricular response?
A) Defibrillation
B) Synchronized cardioversion
C) Vagal maneuvers
D) Administration of amiodarone
What rhythm is characterized by no P waves, irregularly irregular rhythm, and a fibrillatory baseline?
A) Atrial flutter
B) Atrial fibrillation
C) Ventricular fibrillation
D) Junctional rhythm
Which electrolyte imbalance can cause tall, peaked T waves on the EKG?
A) Hypokalemia
B) Hyperkalemia
C) Hypocalcemia
D) Hypercalcemia
What is the initial treatment for symptomatic bradycardia?
A) Atropine
B) Amiodarone
C) Lidocaine
D) Defibrillation
Which rhythm has regular, wide QRS complexes and a ventricular rate between 20-40 bpm?
A) Sinus bradycardia
B) Idioventricular rhythm
C) Ventricular fibrillation
D) Junctional rhythm
What does a prolonged QT interval increase the risk of?
A) Torsades de Pointes
B) Atrial fibrillation
C) Ventricular tachycardia
D) Junctional tachycardia
Which heart block is also called a “complete heart block”?
A) First-degree AV block
B) Second-degree AV block Type I
C) Second-degree AV block Type II
D) Third-degree AV block
Which EKG change indicates hypercalcemia?
A) Shortened QT interval
B) Prolonged QT interval
C) Peaked T waves
D) ST segment depression
What is the best intervention for ventricular tachycardia with a pulse?
A) Immediate defibrillation
B) Synchronized cardioversion
C) Vagal maneuvers
D) Chest compressions
Which of the following is most characteristic of premature ventricular contractions (PVCs)?
A) Narrow QRS complex
B) Wide QRS complex
C) Prolonged PR interval
D) Inverted P wave
What rhythm has no discernible P wave, a chaotic baseline, and an irregular ventricular rhythm?
A) Sinus tachycardia
B) Atrial fibrillation
C) Ventricular tachycardia
D) Junctional tachycardia
Which of the following is a hallmark of ventricular fibrillation?
A) Regular QRS complexes
B) Chaotic and disorganized electrical activity
C) Regular ventricular rate
D) P waves before every QRS complex
Which medication is commonly used to manage rate control in atrial fibrillation?
A) Digoxin
B) Lidocaine
C) Atropine
D) Epinephrine
What is the primary concern with prolonged atrial fibrillation?
A) Sudden cardiac arrest
B) Stroke due to embolism
C) Bradycardia
D) Ventricular fibrillation
What is the typical ventricular rate in untreated atrial fibrillation?
A) Less than 60 bpm
B) 60-100 bpm
C) 100-180 bpm
D) Greater than 200 bpm
Which EKG finding is associated with Wolf-Parkinson-White Syndrome?
A) Delta waves
B) Shortened QT interval
C) Prolonged PR interval
D) Peaked T waves
Which rhythm is characterized by grouped beating with dropped QRS complexes?
A) Atrial flutter
B) Second-degree AV block Type II
C) Second-degree AV block Type I
D) Third-degree AV block
What is the preferred treatment for unstable ventricular tachycardia without a pulse?
A) Atropine
B) Defibrillation
C) Synchronized cardioversion
D) Adenosine
What is the normal duration of the PR interval?
A) 0.08-0.12 seconds
B) 0.12-0.20 seconds
C) 0.20-0.30 seconds
D) 0.30-0.40 seconds
Which condition is associated with a sawtooth pattern on the EKG?
A) Atrial fibrillation
B) Atrial flutter
C) Junctional rhythm
D) Ventricular tachycardia
What rhythm is treated with transcutaneous pacing?
A) Atrial fibrillation
B) Third-degree AV block
C) Ventricular fibrillation
D) Sinus tachycardia
What is the hallmark feature of Torsades de Pointes?
A) Polymorphic QRS complexes
B) Narrow QRS complexes
C) Inverted T waves
D) Prolonged PR interval
Which rhythm requires immediate CPR and epinephrine?
A) Sinus bradycardia
B) Pulseless electrical activity (PEA)
C) Supraventricular tachycardia (SVT)
D) Junctional rhythm
Which of the following is true about first-degree AV block?
A) The PR interval is prolonged, but all impulses are conducted
B) The PR interval progressively lengthens until a QRS is dropped
C) No impulses are conducted to the ventricles
D) P waves are absent
Which rhythm is characterized by a rapid, regular rate and a P wave before each QRS complex?
A) Atrial fibrillation
B) Sinus tachycardia
C) Ventricular tachycardia
D) Junctional tachycardia
Which rhythm is characterized by a progressive lengthening of the PR interval until a QRS complex is dropped?
A) First-degree AV block
B) Second-degree AV block Type I (Wenckebach)
C) Second-degree AV block Type II
D) Third-degree AV block
What is the most appropriate initial treatment for a patient in ventricular fibrillation?
A) Synchronized cardioversion
B) Administration of atropine
C) Immediate defibrillation
D) Vagal maneuvers
Which electrolyte imbalance is commonly associated with U waves on the EKG?
A) Hyperkalemia
B) Hypokalemia
C) Hypercalcemia
D) Hypocalcemia
In atrial flutter, what is the typical atrial rate range?
A) 60-100 bpm
B) 100-150 bpm
C) 250-350 bpm
D) 350-450 bpm
Which medication is commonly used to convert supraventricular tachycardia (SVT) to sinus rhythm?
A) Atropine
B) Adenosine
C) Amiodarone
D) Epinephrine
What does a delta wave on the EKG suggest?
A) Myocardial infarction
B) Hyperkalemia
C) Wolff-Parkinson-White syndrome
D) Pericarditis
Which rhythm is characterized by a regular rhythm with a rate of 150-250 bpm and narrow QRS complexes?
A) Atrial fibrillation
B) Ventricular tachycardia
C) Supraventricular tachycardia (SVT)
D) Junctional rhythm
What is the hallmark of a junctional rhythm on an EKG?
A) Inverted or absent P waves
B) Wide QRS complexes
C) Peaked T waves
D) Prolonged QT interval
Which rhythm is characterized by chaotic, irregular electrical activity without identifiable P waves, QRS complexes, or T waves?
A) Atrial fibrillation
B) Ventricular fibrillation
C) Asystole
D) Ventricular tachycardia
What is the treatment of choice for symptomatic sinus bradycardia?
A) Adenosine
B) Atropine
C) Amiodarone
D) Defibrillation
Which rhythm is characterized by a sawtooth pattern of P waves?
A) Atrial fibrillation
B) Atrial flutter
C) Ventricular tachycardia
D) Junctional rhythm
What is the normal duration of the QRS complex?
A) Less than 0.08 seconds
B) Less than 0.10 seconds
C) Less than 0.12 seconds
D) Less than 0.20 seconds
Which rhythm is characterized by three or more consecutive premature ventricular contractions (PVCs) at a rate exceeding 100 bpm?
A) Atrial fibrillation
B) Ventricular tachycardia
C) Supraventricular tachycardia
D) Junctional tachycardia
What is the primary characteristic of asystole on an EKG?
A) Chaotic baseline without discernible waves
B) Regular rhythm with no P waves
C) Flat line without electrical activity
D) Irregular rhythm with wide QRS complexes
Which medication is indicated for the treatment of torsades de pointes?
A) Magnesium sulfate
B) Calcium gluconate
C) Sodium bicarbonate
D) Potassium chloride
Which rhythm is characterized by a regular rhythm with a rate less than 60 bpm and normal P waves preceding each QRS complex?
A) Sinus bradycardia
B) Junctional bradycardia
C) Idioventricular rhythm
D) Atrial fibrillation
What is the distinguishing feature of a first-degree AV block?
A) Progressive lengthening of the PR interval
B) Constant prolonged PR interval
C) Dropped QRS complexes without PR interval changes
D) Complete dissociation between atrial and ventricular activity
Which rhythm is characterized by a ventricular rate of 20-40 bpm, wide QRS complexes, and absence of P waves?
A) Junctional rhythm
B) Idioventricular rhythm
C) Ventricular fibrillation
D) Atrial fibrillation
What is the initial treatment for a stable patient with supraventricular tachycardia (SVT)?
A) Immediate defibrillation
B) Vagal maneuvers
C) Intravenous epinephrine
D) Synchronized cardioversion
What is the distinguishing feature of Third-degree (complete) AV block?
A) Regular PR intervals
B) No relationship between P waves and QRS complexes
C) Dropped QRS complexes
D) Lengthened PR intervals
What does a peaked T wave on an EKG indicate?
A) Hyperkalemia
B) Hypokalemia
C) Hypocalcemia
D) Hypercalcemia
Which condition typically causes a prolonged QT interval?
A) Hypokalemia
B) Hyperkalemia
C) Hypocalcemia
D) Hypercalcemia
What is the primary treatment for stable atrial fibrillation with a rapid ventricular rate?
A) Defibrillation
B) Adenosine
C) Beta-blockers or calcium channel blockers
D) Epinephrine
What is the initial drug of choice for pulseless ventricular tachycardia?
A) Amiodarone
B) Adenosine
C) Epinephrine
D) Lidocaine
Which rhythm is associated with an irregularly irregular pulse?
A) Ventricular tachycardia
B) Atrial fibrillation
C) Atrial flutter
D) Sinus tachycardia
Which rhythm is treated with synchronized cardioversion in an unstable patient?
A) Ventricular fibrillation
B) Atrial fibrillation with rapid ventricular response
C) Pulseless electrical activity
D) Sinus bradycardia
What is the best method to confirm asystole?
A) Verify with a second lead
B) Begin chest compressions immediately
C) Administer epinephrine
D) Start defibrillation
What EKG finding is characteristic of hypercalcemia?
A) Prolonged QT interval
B) Shortened QT interval
C) Peaked T waves
D) Wide QRS complexes
What is the treatment of choice for symptomatic torsades de pointes?
A) Defibrillation
B) Magnesium sulfate
C) Calcium gluconate
D) Atropine
Which dysrhythmia originates in the AV junction with a heart rate of 40-60 bpm?
A) Sinus bradycardia
B) Junctional rhythm
C) Idioventricular rhythm
D) Supraventricular tachycardia
Which EKG change is a hallmark of myocardial ischemia?
A) ST elevation
B) ST depression or T wave inversion
C) Widened QRS complexes
D) Prolonged QT interval
What is the characteristic feature of a ventricular-paced rhythm on an EKG?
A) Narrow QRS complexes
B) Absence of P waves
C) Wide QRS complexes preceded by pacemaker spikes
D) Prolonged PR interval
What is a common cause of sinus tachycardia?
A) Increased vagal tone
B) Hypovolemia
C) Hyperkalemia
D) Hypothermia
Which rhythm is characterized by a chaotic atrial rate of 350-600 bpm?
A) Atrial flutter
B) Atrial fibrillation
C) Ventricular fibrillation
D) Junctional tachycardia
Which dysrhythmia is most likely to progress to ventricular fibrillation if untreated?
A) Ventricular tachycardia
B) Atrial fibrillation
C) Supraventricular tachycardia
D) Sinus bradycardia
Which rhythm shows three or more different P wave morphologies on the EKG?
A) Atrial fibrillation
B) Multifocal atrial tachycardia
C) Junctional rhythm
D) Sinus arrhythmia
What is the classic treatment for unstable ventricular tachycardia?
A) Defibrillation
B) Synchronized cardioversion
C) Amiodarone infusion
D) Atropine
What is the defining feature of pulseless electrical activity (PEA)?
A) Organized rhythm without a pulse
B) No electrical activity
C) Chaotic electrical activity
D) Asystole with occasional electrical activity
What is the hallmark of an acute pericarditis EKG?
A) PR segment depression
B) ST segment elevation in multiple leads
C) Wide QRS complexes
D) Peaked T waves
Which rhythm is described as a ventricular rate exceeding 100 bpm with a broad, monomorphic QRS?
A) Ventricular fibrillation
B) Ventricular tachycardia
C) Idioventricular rhythm
D) Supraventricular tachycardia
Which dysrhythmia is commonly associated with digitalis toxicity?
A) Sinus bradycardia
B) Atrial tachycardia with block
C) Ventricular fibrillation
D) Junctional tachycardia
Which condition requires immediate defibrillation?
A) Asystole
B) Pulseless ventricular tachycardia
C) First-degree AV block
D) Sinus bradycardia
What is the treatment for symptomatic bradycardia when atropine is ineffective?
A) Adenosine
B) Transcutaneous pacing
C) Amiodarone
D) Defibrillation
Which EKG change is associated with pulmonary embolism?
A) S1Q3T3 pattern
B) ST elevation in leads II, III, and aVF
C) Wide QRS complexes
D) Inverted T waves in precordial leads
Which rhythm is characterized by a sawtooth pattern on the EKG?
A) Atrial flutter
B) Atrial fibrillation
C) Junctional tachycardia
D) Ventricular tachycardia
Which dysrhythmia is commonly seen after a myocardial infarction?
A) Ventricular fibrillation
B) First-degree AV block
C) Sinus tachycardia
D) Multifocal atrial tachycardia
What is the usual heart rate range in accelerated idioventricular rhythm (AIVR)?
A) 40-60 bpm
B) 60-100 bpm
C) 100-120 bpm
D) Over 120 bpm
Which medication is used to terminate paroxysmal supraventricular tachycardia (PSVT)?
A) Adenosine
B) Amiodarone
C) Digoxin
D) Atropine
What is the initial step in treating sinus tachycardia?
A) Administer beta-blockers
B) Identify and treat the underlying cause
C) Perform synchronized cardioversion
D) Administer adenosine
What is the hallmark of Wolff-Parkinson-White syndrome on an EKG?
A) Shortened PR interval and delta wave
B) Prolonged QT interval
C) Wide QRS complexes without P waves
D) Peaked T waves
Which rhythm is characterized by P waves of varying morphology and irregular PR intervals?
A) Atrial flutter
B) Multifocal atrial tachycardia
C) Junctional rhythm
D) Atrial fibrillation
What is the typical treatment for symptomatic first-degree AV block?
A) No treatment is typically needed
B) Administer atropine
C) Perform synchronized cardioversion
D) Initiate pacemaker therapy
What is the treatment for asystole?
A) Defibrillation
B) Epinephrine and high-quality CPR
C) Amiodarone
D) Synchronized cardioversion
Which dysrhythmia has a characteristic “wide and bizarre” QRS complex without preceding P waves?
A) Premature ventricular contraction (PVC)
B) Supraventricular tachycardia
C) Junctional escape rhythm
D) Ventricular fibrillation
Which rhythm often occurs in response to hypothermia?
A) Junctional rhythm
B) Atrial fibrillation
C) Idioventricular rhythm
D) Sinus bradycardia
What is the purpose of synchronized cardioversion?
A) To terminate rhythms like ventricular fibrillation
B) To reset the SA node during tachyarrhythmias
C) To speed up bradycardic rhythms
D) To treat pulseless electrical activity
Which medication is contraindicated in bradycardia with second-degree type II AV block?
A) Atropine
B) Epinephrine
C) Adenosine
D) Amiodarone
Which rhythm is most likely to occur in patients with hypothermia?
A) Sinus tachycardia
B) Atrial flutter
C) Junctional rhythm
D) Osborn waves
What is the typical appearance of ventricular fibrillation on an EKG?
A) Irregular baseline with no identifiable QRS complexes
B) Rapid, regular QRS complexes
C) Wide QRS complexes with prolonged QT interval
D) Sawtooth baseline with irregular QRS complexes
What condition is often indicated by ST segment depression in leads V1-V4?
A) Posterior myocardial infarction
B) Anterior myocardial infarction
C) Lateral myocardial infarction
D) Inferior myocardial infarction
Which lead is most commonly used to detect atrial activity on an EKG?
A) Lead I
B) Lead II
C) Lead V6
D) Lead aVL
What rhythm has a ventricular rate of less than 40 bpm with no P waves?
A) Accelerated junctional rhythm
B) Idioventricular rhythm
C) Sinus bradycardia
D) Third-degree AV block
What is the treatment for hemodynamically unstable ventricular fibrillation?
A) Synchronized cardioversion
B) Immediate defibrillation
C) Adenosine
D) Beta-blockers
What does an EKG with prominent U waves typically indicate?
A) Hyperkalemia
B) Hypokalemia
C) Hypercalcemia
D) Hypocalcemia
Which dysrhythmia has a heart rate of 60-100 bpm and no visible P waves?
A) Sinus tachycardia
B) Accelerated junctional rhythm
C) Ventricular fibrillation
D) Idioventricular rhythm
Which EKG change suggests early myocardial infarction?
A) ST elevation
B) ST depression
C) Prolonged QT interval
D) Inverted T waves
Which rhythm is often caused by electrolyte imbalances or hypoxia in infants?
A) Sinus arrhythmia
B) Premature atrial contractions
C) Ventricular tachycardia
D) Atrial fibrillation
Which rhythm is treated with atropine for bradycardia?
A) Sinus bradycardia
B) Junctional escape rhythm
C) Third-degree AV block
D) Ventricular fibrillation
What is the recommended intervention for unstable SVT?
A) Immediate defibrillation
B) Vagal maneuvers followed by synchronized cardioversion
C) Atropine
D) IV magnesium sulfate
What is the primary characteristic of Torsades de Pointes on an EKG?
A) Narrow QRS complexes with a sawtooth baseline
B) Polymorphic QRS complexes that twist around the baseline
C) Regular rhythm with absent P waves
D) Wide QRS complexes with a flat baseline
Which electrolyte imbalance is most commonly associated with Torsades de Pointes?
A) Hypocalcemia
B) Hyperkalemia
C) Hypomagnesemia
D) Hypernatremia
What does the PR interval represent on an EKG?
A) Atrial depolarization and conduction through the AV node
B) Ventricular depolarization
C) Ventricular repolarization
D) Total electrical activity of the heart
Which condition is associated with a widened QRS complex greater than 0.12 seconds?
A) First-degree AV block
B) Bundle branch block
C) Sinus tachycardia
D) Atrial fibrillation
What is the most common cause of premature atrial contractions (PACs)?
A) Myocardial infarction
B) Electrolyte imbalance
C) Caffeine or stress
D) Heart failure
Which rhythm is characterized by an absence of P waves, irregular R-R intervals, and fibrillatory baseline waves?
A) Atrial flutter
B) Atrial fibrillation
C) Ventricular tachycardia
D) Junctional rhythm
What is the initial treatment for symptomatic bradycardia?
A) Synchronized cardioversion
B) Atropine 0.5 mg IV
C) Defibrillation
D) IV amiodarone
Which rhythm is associated with a ventricular rate greater than 150 bpm and narrow QRS complexes?
A) Atrial flutter
B) Paroxysmal supraventricular tachycardia (PSVT)
C) Ventricular tachycardia
D) Idioventricular rhythm
What is the hallmark EKG feature of a junctional rhythm?
A) Prolonged PR interval
B) P waves inverted, absent, or after QRS complexes
C) Tall, peaked T waves
D) Fibrillatory baseline waves
What is the first-line treatment for ventricular fibrillation?
A) Synchronized cardioversion
B) High-quality CPR and defibrillation
C) IV adenosine
D) Beta-blockers
What rhythm is characterized by grouped beating and progressively lengthening PR intervals?
A) Second-degree AV block, Mobitz type I (Wenckebach)
B) Second-degree AV block, Mobitz type II
C) Third-degree AV block
D) Junctional escape rhythm
What is the primary cause of pulseless electrical activity (PEA)?
A) Myocardial infarction
B) Hypoxia, hypovolemia, or acidosis
C) Hypercalcemia
D) Torsades de Pointes
Which rhythm typically requires pacemaker implantation?
A) First-degree AV block
B) Sinus bradycardia
C) Third-degree AV block
D) Atrial flutter
What rhythm is associated with “R on T” phenomenon?
A) Torsades de Pointes
B) Ventricular fibrillation
C) Premature ventricular contractions (PVCs)
D) Sinus tachycardia
What is the usual treatment for multifocal atrial tachycardia (MAT)?
A) IV beta-blockers or calcium channel blockers
B) Adenosine
C) Synchronized cardioversion
D) IV magnesium sulfate
What does an EKG with a prolonged QT interval indicate?
A) Hyperkalemia
B) Risk for Torsades de Pointes
C) Atrial fibrillation
D) Supraventricular tachycardia
What rhythm has a constant PR interval with intermittent dropped QRS complexes?
A) Second-degree AV block, Mobitz type II
B) Second-degree AV block, Mobitz type I
C) Third-degree AV block
D) Junctional escape rhythm
Which leads are typically used to detect inferior myocardial infarction?
A) Leads I, aVL
B) Leads II, III, aVF
C) Leads V1-V4
D) Leads V5, V6
What is a common feature of hyperkalemia on an EKG?
A) Flattened T waves
B) Peaked T waves
C) Widened PR intervals
D) Prolonged QT intervals
What rhythm is most often caused by digitalis toxicity?
A) Atrial fibrillation
B) Ventricular tachycardia
C) Junctional rhythm
D) Atrial tachycardia with block
Which rhythm has irregularly irregular R-R intervals and absence of P waves?
A) Ventricular fibrillation
B) Atrial fibrillation
C) Junctional rhythm
D) Atrial flutter
What is the hallmark of ventricular tachycardia (VT)?
A) Narrow QRS complexes
B) Wide QRS complexes with regular rhythm
C) Irregular R-R intervals with fibrillatory baseline waves
D) Progressive PR interval prolongation
What rhythm results from reentry within the AV node?
A) Atrial flutter
B) AV nodal reentrant tachycardia (AVNRT)
C) Ventricular tachycardia
D) Idioventricular rhythm
Which EKG abnormality is typically associated with pericarditis?
A) ST elevation in all leads
B) ST depression in leads II, III, and aVF
C) Peaked T waves
D) Flattened P waves
What does a complete heart block (third-degree AV block) typically show on an EKG?
A) Prolonged PR interval with grouped beats
B) No association between P waves and QRS complexes
C) Narrow QRS complexes with fast rate
D) Irregular R-R intervals
NCLEX Dysrhythmias & EKG Interpretation Questions and Answers for Study Guide
Explain the physiological basis of sinus bradycardia and discuss the clinical significance, common causes, and appropriate nursing interventions.
Answer:
Sinus bradycardia is a rhythm originating from the sinoatrial (SA) node with a heart rate of fewer than 60 beats per minute. The physiological basis involves slower automaticity of the SA node, resulting in delayed impulse generation. While it can be normal in well-trained athletes or during sleep, it may also indicate an underlying pathology.
Clinical Significance:
Sinus bradycardia can reduce cardiac output, leading to symptoms such as dizziness, syncope, fatigue, or hypotension. Severe bradycardia can result in inadequate perfusion to vital organs.
Common Causes:
- Increased vagal tone (e.g., during sleep or in athletes)
- Medications such as beta-blockers, calcium channel blockers, or digoxin
- Conditions like hypothyroidism, myocardial infarction, or sick sinus syndrome
Nursing Interventions:
- Monitor vital signs and assess for symptoms of reduced perfusion (e.g., altered mental status or hypotension).
- Administer atropine (0.5 mg IV) for symptomatic bradycardia.
- If atropine is ineffective, prepare for transcutaneous pacing or infusion of dopamine/epinephrine.
- Educate the patient on avoiding vagal maneuvers that may exacerbate bradycardia.
Describe atrial fibrillation (AF), including its EKG characteristics, potential complications, and nursing management strategies.
Answer:
Atrial fibrillation (AF) is an arrhythmia characterized by rapid and disorganized electrical impulses in the atria, leading to an irregularly irregular ventricular response.
EKG Characteristics:
- Absence of distinct P waves; instead, there are fibrillatory waves (f-waves).
- Irregular R-R intervals.
- A variable ventricular rate depending on AV node conduction.
Potential Complications:
- Thromboembolism: Ineffective atrial contraction can lead to blood stasis and clot formation, increasing the risk of stroke.
- Rapid ventricular response: This may compromise cardiac output, leading to heart failure or ischemia.
Nursing Management Strategies:
- Administer rate-controlling medications such as beta-blockers, calcium channel blockers (e.g., diltiazem), or digoxin.
- Initiate anticoagulation therapy (e.g., warfarin, DOACs) to prevent stroke.
- Monitor for symptoms of reduced cardiac output and educate the patient on recognizing signs of stroke.
- Prepare the patient for elective cardioversion or consider antiarrhythmic drugs if rhythm control is the goal.
Analyze the differences between ventricular tachycardia (VT) and ventricular fibrillation (VF) in terms of pathophysiology, clinical presentation, and treatment approaches.
Answer:
Pathophysiology:
- Ventricular Tachycardia (VT): Characterized by a rapid rhythm originating from ectopic foci in the ventricles. It can be monomorphic (uniform QRS complexes) or polymorphic (varied QRS morphologies).
- Ventricular Fibrillation (VF): A chaotic and disorganized rhythm caused by multiple ectopic impulses in the ventricles, resulting in no effective cardiac contraction.
Clinical Presentation:
- VT: Patients may experience palpitations, dizziness, chest pain, or syncope. Sustained VT can lead to hemodynamic instability and cardiac arrest.
- VF: Always results in cardiac arrest with no palpable pulse, respirations, or consciousness.
Treatment Approaches:
- VT: If stable, administer antiarrhythmic drugs (e.g., amiodarone or procainamide). If unstable, perform synchronized cardioversion. Pulseless VT requires immediate defibrillation and CPR.
- VF: Initiate high-quality CPR and deliver defibrillation as soon as possible. Follow the Advanced Cardiac Life Support (ACLS) algorithm, including epinephrine and amiodarone.
Discuss the nursing implications of QT interval prolongation, including its causes, potential complications, and preventive measures.
Answer:
The QT interval represents the time for ventricular depolarization and repolarization. Prolongation (>0.44 seconds in males, >0.46 seconds in females) increases the risk of Torsades de Pointes, a potentially fatal arrhythmia.
Causes:
- Electrolyte imbalances: Hypokalemia, hypomagnesemia, or hypocalcemia.
- Medications: Antiarrhythmics (e.g., amiodarone), antipsychotics, and certain antibiotics (e.g., macrolides).
- Congenital long QT syndrome.
Potential Complications:
- Torsades de Pointes, leading to ventricular fibrillation and cardiac arrest.
Preventive Measures:
- Monitor serum electrolyte levels and correct abnormalities promptly.
- Avoid medications that prolong the QT interval in at-risk patients.
- Perform regular EKG monitoring for patients on QT-prolonging drugs.
- Educate patients about the importance of adhering to follow-up care.
Explain the clinical significance of ST elevation on an EKG, differentiating between STEMI and other causes of ST elevation.
Answer:
ST elevation on an EKG suggests myocardial injury and is a hallmark of ST-elevation myocardial infarction (STEMI). However, not all ST elevations indicate STEMI.
STEMI:
- Caused by complete occlusion of a coronary artery.
- ST elevation is typically ≥1 mm in two contiguous leads.
- Requires immediate reperfusion therapy, including percutaneous coronary intervention (PCI) or thrombolysis.
Other Causes of ST Elevation:
- Pericarditis: Diffuse ST elevation with PR depression.
- Early repolarization: Seen in young, healthy individuals with concave ST elevation.
- Left ventricular aneurysm: Persistent ST elevation weeks after a myocardial infarction.
Nursing Implications:
- Recognize ST elevation patterns and notify the healthcare provider immediately.
- Obtain serial EKGs and monitor cardiac biomarkers (e.g., troponin).
- Provide oxygen, administer nitroglycerin (if not contraindicated), and prepare the patient for PCI.
- Educate the patient on lifestyle changes to reduce future cardiovascular risk.
Describe the nursing assessment and interventions for a patient experiencing third-degree heart block.
Answer:
Third-degree heart block, also known as complete heart block, occurs when there is no conduction of electrical impulses from the atria to the ventricles, leading to independent atrial and ventricular rhythms.
Nursing Assessment:
- EKG Characteristics: Regular P waves and QRS complexes, but they occur independently of each other. The ventricular rate is typically slow (20–40 bpm).
- Symptoms: Hypotension, dizziness, syncope, chest pain, or signs of heart failure.
- Assess for decreased cardiac output (e.g., weak pulses, cyanosis, altered mental status).
Nursing Interventions:
- Ensure airway, breathing, and circulation (ABCs). Administer oxygen as needed.
- Monitor vital signs and initiate continuous cardiac monitoring.
- If symptomatic, prepare for temporary pacing (e.g., transcutaneous pacing).
- Administer atropine (may be ineffective in complete heart block) and consider vasopressors if hypotension persists.
- Educate the patient and family about the potential need for permanent pacemaker placement.
Compare and contrast supraventricular tachycardia (SVT) and junctional rhythms in terms of causes, EKG features, and management.
Answer:
Supraventricular Tachycardia (SVT):
- Causes: Emotional stress, caffeine, electrolyte imbalances, or accessory pathway disorders (e.g., Wolff-Parkinson-White syndrome).
- EKG Features: Narrow QRS complexes, heart rate >150 bpm, and P waves may be hidden within the T waves.
- Management: Vagal maneuvers, adenosine administration, or synchronized cardioversion if unstable. Beta-blockers or calcium channel blockers may be used for rate control.
Junctional Rhythms:
- Causes: SA node dysfunction, digoxin toxicity, or ischemia.
- EKG Features: Narrow QRS complexes, absent or inverted P waves, and a ventricular rate of 40–60 bpm (accelerated junctional rhythm: 60–100 bpm).
- Management: Treat the underlying cause, monitor for symptoms, and consider atropine or pacing if symptomatic.
Comparison:
- Both are narrow-complex rhythms but differ in heart rate and P wave visibility.
- SVT typically requires acute rate control, whereas junctional rhythms often require investigation and correction of underlying causes.
Discuss the nursing role in patient education for individuals with newly diagnosed atrial flutter.
Answer:
Atrial flutter is a supraventricular arrhythmia characterized by a rapid, regular atrial rate (250–350 bpm) with a “sawtooth” pattern on the EKG. Proper patient education is crucial for management and prevention of complications.
Nursing Role in Education:
- Disease Understanding:
- Explain the nature of atrial flutter and its impact on heart function.
- Discuss the potential for progression to atrial fibrillation and associated risks.
- Medications:
- Educate on rate-controlling drugs (e.g., beta-blockers or calcium channel blockers) and anticoagulation therapy to prevent stroke.
- Emphasize adherence to prescribed medications and monitoring for side effects.
- Lifestyle Modifications:
- Encourage avoiding triggers such as alcohol, caffeine, and smoking.
- Promote a heart-healthy diet, regular exercise, and weight management.
- Symptom Recognition:
- Teach the patient to recognize signs of poor cardiac output (e.g., dizziness, chest pain) and when to seek medical attention.
- Follow-Up Care:
- Stress the importance of regular follow-up appointments and EKG monitoring.
- Discuss possible interventions like catheter ablation if medical therapy is insufficient.
Explain the nursing priorities for a patient experiencing Torsades de Pointes.
Answer:
Torsades de Pointes (TdP) is a specific type of polymorphic ventricular tachycardia associated with prolonged QT intervals. It is life-threatening and requires immediate intervention.
Nursing Priorities:
- Immediate Actions:
- Ensure the patient has a patent airway and initiate high-quality CPR if pulseless.
- Defibrillate if TdP degenerates into ventricular fibrillation.
- Correct Underlying Causes:
- Administer intravenous magnesium sulfate to stabilize the cardiac membrane.
- Treat electrolyte imbalances (e.g., hypokalemia or hypomagnesemia).
- Discontinue QT-prolonging medications.
- Monitoring:
- Initiate continuous cardiac monitoring to observe for recurring episodes.
- Monitor QT intervals and assess for hemodynamic stability.
- Long-Term Care:
- Educate the patient on avoiding QT-prolonging drugs and maintaining electrolyte balance.
- Discuss the possibility of pacemaker or implantable cardioverter-defibrillator (ICD) placement for recurrent episodes.
Discuss the challenges in diagnosing and managing a patient with Wolff-Parkinson-White (WPW) syndrome.
Answer:
Wolff-Parkinson-White syndrome is a pre-excitation disorder caused by an accessory pathway (Bundle of Kent) that allows early depolarization of the ventricles.
Challenges in Diagnosis:
- EKG findings can mimic other conditions, such as ventricular tachycardia.
- The classic EKG features (short PR interval, delta wave, and wide QRS complexes) may not always be evident.
- Patients may present asymptomatically or with episodes of palpitations, dizziness, or syncope.
Management Challenges:
- Episodes of tachyarrhythmias (e.g., atrioventricular reentrant tachycardia [AVRT]) require rapid intervention.
- Adenosine or AV nodal-blocking agents are contraindicated in WPW with atrial fibrillation due to the risk of ventricular fibrillation.
- Definitive treatment often requires catheter ablation, but access to specialized care may delay intervention.
Nursing Role in Management:
- Educate the patient on recognizing symptoms of tachyarrhythmias and when to seek emergency care.
- Provide emotional support and education about the benefits and risks of catheter ablation.
- Monitor for arrhythmias during acute episodes and ensure readiness for emergency interventions.
Explain the role of defibrillation in treating ventricular fibrillation and the steps to ensure effective defibrillation.
Answer:
Ventricular fibrillation (VF) is a life-threatening arrhythmia characterized by disorganized, chaotic electrical activity in the heart, leading to ineffective contractions and cessation of cardiac output. Defibrillation is the definitive treatment to restore a viable rhythm.
Role of Defibrillation:
- It delivers a controlled electrical shock to depolarize the heart muscle uniformly, allowing the sinoatrial (SA) node to regain control as the primary pacemaker.
- It is most effective when performed immediately after VF onset.
Steps to Ensure Effective Defibrillation:
- Prepare the Patient:
- Confirm the absence of a pulse and initiate CPR.
- Ensure the patient is dry and free of conductive materials to avoid burns.
- Select the Right Equipment and Settings:
- Use a biphasic defibrillator set to the recommended energy level (typically 120–200 joules for adults).
- Placement of Pads:
- Place one pad below the right clavicle and the other on the left lateral chest wall.
- Clear the Area:
- Ensure no one is in contact with the patient or the bed.
- Shock Delivery:
- Administer the shock and immediately resume CPR for 2 minutes.
- Reassess rhythm and pulse after CPR cycles.
- Ongoing Care:
- Treat underlying causes (e.g., hypoxia, electrolyte imbalances).
- Administer medications like epinephrine or amiodarone if VF persists.
Discuss the nursing interventions for a patient with bradycardia and hemodynamic instability.
Answer:
Bradycardia is a slow heart rate (<60 bpm) that can lead to insufficient cardiac output and organ perfusion if symptomatic.
Nursing Interventions:
- Initial Assessment:
- Check for signs of instability: hypotension, altered mental status, chest pain, or dyspnea.
- Obtain a 12-lead EKG to identify the underlying rhythm (e.g., sinus bradycardia, heart block).
- Interventions:
- Airway and Breathing: Provide oxygen if oxygen saturation is <94%.
- Pharmacological Treatment:
- Administer atropine (0.5 mg IV every 3–5 minutes, up to 3 mg total).
- Consider dopamine or epinephrine infusion if atropine is ineffective.
- Electrical Therapy:
- Prepare for transcutaneous pacing if the patient remains unstable.
- Monitor for Complications:
- Observe for worsening bradycardia or progression to asystole.
- Continuously monitor vital signs and cardiac rhythm.
- Long-Term Considerations:
- Investigate and address reversible causes (e.g., medications, electrolyte imbalances).
- Educate the patient about potential pacemaker placement if indicated.
Analyze the risks and benefits of using amiodarone for ventricular arrhythmias.
Answer:
Amiodarone is a Class III antiarrhythmic used to treat life-threatening ventricular arrhythmias, including ventricular tachycardia (VT) and ventricular fibrillation (VF).
Benefits:
- Efficacy: Effective in terminating ventricular arrhythmias and reducing recurrence.
- Versatility: Can be used intravenously for acute arrhythmias or orally for long-term maintenance.
- Prolonged Action: Long half-life allows for sustained effects after discontinuation.
Risks:
- Cardiac Side Effects: Bradycardia, QT prolongation, and risk of torsades de pointes.
- Non-Cardiac Toxicity: Pulmonary fibrosis, hepatotoxicity, thyroid dysfunction, and skin discoloration.
- Drug Interactions: Potential interactions with anticoagulants, digoxin, and other QT-prolonging medications.
Nursing Implications:
- Monitor cardiac rhythm and QT interval regularly.
- Assess for signs of toxicity, including respiratory symptoms and liver dysfunction.
- Educate patients on adherence and the importance of regular follow-ups for laboratory testing.
Describe the EKG changes observed in acute myocardial infarction and their significance.
Answer:
Acute myocardial infarction (AMI) results from ischemia and necrosis of the myocardial tissue, often reflected by characteristic changes on the EKG.
EKG Changes:
- ST-Elevation Myocardial Infarction (STEMI):
- ST-Segment Elevation: Indicates complete occlusion of a coronary artery.
- Reciprocal Changes: ST depression in opposite leads.
- Pathologic Q Waves: Develop later, signifying necrosis.
- Non-ST-Elevation Myocardial Infarction (NSTEMI):
- ST-Segment Depression or T Wave Inversion: Indicates partial occlusion.
Significance:
- Early recognition of EKG changes allows prompt intervention (e.g., thrombolysis, percutaneous coronary intervention).
- Monitoring for complications such as arrhythmias or heart block is crucial.
Nursing Role:
- Administer oxygen, aspirin, and nitroglycerin as ordered.
- Monitor serial EKGs and cardiac biomarkers (e.g., troponins).
- Educate the patient on risk factors and lifestyle modifications to prevent recurrence.
Explain the pathophysiology and EKG findings of hyperkalemia.
Answer:
Hyperkalemia refers to an elevated serum potassium level (>5.0 mEq/L), which disrupts cardiac conduction and contractility.
Pathophysiology:
- High extracellular potassium reduces the resting membrane potential, leading to decreased myocardial excitability and slowed conduction.
- Severe hyperkalemia can result in life-threatening arrhythmias or asystole.
EKG Findings:
- Mild Hyperkalemia:
- Peaked T waves.
- Shortened QT interval.
- Moderate Hyperkalemia:
- Widened QRS complex.
- Flattened P waves or loss of P waves.
- Severe Hyperkalemia:
- Sinusoidal wave pattern leading to ventricular fibrillation or asystole.
Nursing Management:
- Administer calcium gluconate to stabilize the myocardium.
- Use insulin with glucose to shift potassium into cells.
- Consider dialysis for refractory cases.