WorksheetsNCLEX EKG QUESTIONS
Total questions: 100
Worksheet time: 50mins
Which ECG findings indicate normal sinus rhythm? Select all that apply.
Heart rate 76 bpm
One P wave before every QRS
PR interval 0.14 seconds
QRS duration 0.14 seconds
Regular R-to-R intervals
Which structure normally initiates the electrical impulse in normal sinus rhythm?
AV node
Bundle of His
SA node
Purkinje fibers
A nurse measures a PR interval of 0.18 seconds. How should this be interpreted?
Abnormally prolonged
Abnormally shortened
Normal
Indicates complete heart block
Which ECG finding best confirms that conduction is following a sinus rhythm pattern?
No P waves visible
One P wave for each QRS
PR interval not measurable
QRS complexes wider than 0.12 seconds
A patient’s ECG shows: HR 88, regular rhythm, P before every QRS, PR 0.16, QRS 0.08. How should the nurse document this rhythm?
Sinus bradycardia
Normal sinus rhythm
Sinus tachycardia
Atrial fibrillation
The nurse is teaching ECG interpretation. Which PR interval is within normal limits?
0.10 seconds
0.12 seconds
0.22 seconds
0.28 seconds
The nurse is verifying the QRS duration. Which value is considered normal?
0.06 seconds
0.14 seconds
0.18 seconds
0.22 seconds
Which statement about sinus rhythms is accurate?
Sinus rhythms always have absent P waves
Sinus rhythms have a regular rhythm with normal PR/QRS/QT intervals
Sinus rhythms are always dangerous and require immediate cardioversion
Sinus rhythm originates from the ventricles
The nurse is analyzing an ECG strip. Which step should be performed first when interpreting any rhythm?
Determine whether the rhythm is regular or irregular
Identify ST segment elevation
Calculate QT interval first
Determine presence of U waves
Which ECG component represents ventricular depolarization?
P wave
PR interval
QRS complex
QT interval
A patient’s rhythm is sinus with a rate of 52 bpm. Which documentation is most appropriate?
Normal sinus rhythm
Sinus bradycardia
Sinus tachycardia
Junctional rhythm
Which are potential causes of sinus bradycardia? Select all that apply.
Vagal stimulation
Hypothermia
Beta-blocker use
Hypovolemia
Hypothyroidism
The nurse is caring for a patient with sinus bradycardia. Which assessment finding most strongly suggests poor perfusion?
Warm skin and bounding pulses
Dizziness and hypotension
Heart rate 58 with no symptoms
Mild anxiety
A patient with sinus bradycardia is symptomatic. Which medication is typically the first-line treatment?
Adenosine
Atropine
Amiodarone
Diltiazem
The nurse gives atropine for symptomatic bradycardia. What is the expected physiologic effect?
Slows SA node firing
Increases vagal tone
Blocks vagal tone and increases SA node firing
Immediately defibrillates the heart
A patient with sinus bradycardia does not respond to atropine and remains hypotensive. Which intervention should the nurse anticipate next? Select all that apply.
Transcutaneous pacing
Dopamine infusion
Epinephrine infusion
Adenosine IV push
Vagal maneuvers
Sinus bradycardia is present with HR 48, but the patient is alert, BP stable, and denies symptoms. What is the priority nursing action?
Prepare for immediate cardioversion
Administer atropine now
Continue monitoring and assess for symptoms
Start CPR
Which patient is most likely to have sinus bradycardia as a normal finding?
A febrile patient with dehydration
A patient with uncontrolled pain
An endurance athlete at rest
A patient with acute hypoxia
The nurse notes sinus bradycardia after a patient performs a Valsalva maneuver. Which explanation is most accurate?
Valsalva increases sympathetic tone
Valsalva increases vagal stimulation, slowing the SA node
Valsalva causes ventricular ectopy
Valsalva shortens the PR interval
The nurse is giving shift report. Which statement best describes why sinus bradycardia can be clinically significant?
It always causes ventricular fibrillation
It can decrease cardiac output and cause fatigue/dizziness
It indicates atrial fibrillation is present
It confirms the patient needs defibrillation
Which ECG findings are consistent with sinus tachycardia? Select all that apply.
Heart rate 128 bpm
Regular rhythm
One P wave before every QRS
PR interval not measurable
QRS duration within normal limits
Which statement best describes sinus tachycardia?
It originates from an ectopic ventricular focus
It is usually a primary cardiac problem
It is often a response to an underlying condition
It always requires cardioversion
Which conditions are common causes of sinus tachycardia? Select all that apply.
Fever
Pain
Hypovolemia
Complete heart block
Anxiety
A patient has sinus tachycardia with a heart rate of 118 bpm. What is the priority nursing action?
Prepare for synchronized cardioversion
Administer adenosine immediately
Assess for underlying causes such as pain or fever
Begin CPR
Which ECG feature helps differentiate sinus tachycardia from SVT?
Wide QRS complexes
Presence of visible P waves before each QRS
Heart rate greater than 100 bpm
ST segment elevation
A nurse notes a regular rhythm at 160 bpm with no visible P waves. Which rhythm is most likely?
Sinus tachycardia
Atrial fibrillation
Paroxysmal supraventricular tachycardia (PSVT)
Ventricular tachycardia
Which heart rate range is most consistent with sinus tachycardia?
60–100 bpm
101–180 bpm
150–250 bpm
Greater than 250 bpm
Which statement about treatment of sinus tachycardia is correct?
Cardioversion is always the first-line treatment
Treatment focuses on correcting the underlying cause
Defibrillation is required
Pacemaker insertion is indicated
Which medications may be used to manage sinus tachycardia when clinically indicated? Select all that apply.
Beta blockers
Calcium channel blockers
Adenosine
Atropine
Epinephrine
Why may adenosine be given to a patient initially thought to have sinus tachycardia?
To permanently slow the heart rate
To terminate ventricular tachycardia
To help differentiate sinus tachycardia from SVT
To increase cardiac output
Which patient with sinus tachycardia would require the most urgent intervention?
HR 110 bpm after walking
HR 120 bpm with fever
HR 140 bpm with hypotension and altered mental status
HR 105 bpm with anxiety
Which assessment findings suggest decreased cardiac output related to sinus tachycardia? Select all that apply.
Dizziness
Hypotension
Fatigue
Bounding peripheral pulses
Warm, flushed skin
A patient with sinus tachycardia is hemodynamically unstable. Which intervention may be required?
Vagal maneuvers
Synchronized cardioversion
Observation only
Oral beta blocker
Why is synchronized cardioversion preferred over defibrillation in unstable sinus tachycardia?
It delivers a higher energy shock
It avoids delivering the shock on the R wave
It delivers the shock synchronized with the R wave
It is used only for ventricular rhythms
Which statement about sinus tachycardia and myocardial oxygen demand is accurate?
Sinus tachycardia decreases oxygen demand
It has no effect on oxygen consumption
It increases myocardial oxygen demand
It improves coronary perfusion
A patient with anemia develops sinus tachycardia. What is the best explanation?
The SA node is damaged
The heart is compensating for reduced oxygen-carrying capacity
Ventricular ectopy is present
The AV node is pacing the heart
Which finding supports that a rhythm is sinus tachycardia and not atrial fibrillation?
Irregularly irregular rhythm
Absence of P waves
Regular R-to-R intervals
Ventricular rate greater than 140 bpm
Which patient teaching is most appropriate for a patient prone to sinus tachycardia?
Avoid all physical activity
Monitor for triggers such as caffeine and stress
Prepare for pacemaker insertion
Expect lifelong anticoagulation
A nurse compares today’s ECG to one from three days ago. Why is this comparison important?
Sinus tachycardia never changes
ECG trends help identify acute changes or deterioration
Older ECGs are more accurate
Only ST elevation can be identified this way
Which statement best summarizes sinus tachycardia?
A lethal dysrhythmia requiring immediate defibrillation
A rhythm that always originates below the AV node
A compensatory response that signals an underlying problem
A rhythm that requires permanent pacing
Which ECG findings are characteristic of SVT? Select all that apply.
Heart rate 160 bpm
Regular R-to-R intervals
P waves clearly visible before each QRS
Narrow QRS complexes
Abrupt onset and termination
SVT most commonly occurs due to which mechanism?
Failure of the SA node to fire
Re-entry circuit involving the AV node
Multiple ectopic atrial sites firing chaotically
Ventricular ectopic focus
Which heart rate range is most consistent with SVT?
60–100 bpm
101–180 bpm
150–250 bpm
Greater than 300 bpm
Which feature best differentiates SVT from sinus tachycardia?
Heart rate above 150 bpm
Presence of chest pain
Abrupt onset and termination
Regular rhythm
Which clinical situations are associated with SVT? Select all that apply.
Emotional stress
Caffeine or tobacco use
Deep inspiration
Complete heart block
Digitalis toxicity
A patient presents with palpitations and dizziness. ECG shows HR 170 bpm, regular rhythm, narrow QRS, no visible P waves. Which rhythm is most likely?
Sinus tachycardia
Atrial fibrillation
SVT
Ventricular tachycardia
The nurse attempts vagal maneuvers for SVT. Which actions are appropriate? Select all that apply.
Valsalva maneuver
Coughing
Carotid sinus massage (with provider order)
Ice pack to the face/neck
Trendelenburg positioning
Why are vagal maneuvers effective in treating SVT?
They increase sympathetic stimulation
They slow conduction through the AV node
They terminate ventricular ectopy
They suppress the SA node permanently
A patient remains in SVT after vagal maneuvers. Which medication is first-line for a hemodynamically stable patient?
Amiodarone
Digoxin
Adenosine
Epinephrine
When administering adenosine, which nursing action is most important?
Infuse slowly over 10 minutes
Administer through a peripheral IV without flush
Push rapidly followed by a rapid saline flush
Place the patient supine for 30 minutes after
Which patient statement should the nurse anticipate after adenosine administration?
I feel no different.
My heart feels like it stopped for a moment.
I feel numbness in my legs.
I feel chest tightness that lasts 30 minutes.
Adenosine works by which mechanism?
Blocking sodium channels
Increasing myocardial contractility
Temporarily blocking AV node conduction
Suppressing ventricular automaticity
Which condition is required before administering adenosine?
Patient must be pulseless
Patient must be hemodynamically stable
Patient must have atrial fibrillation
Patient must be hypotensive
A patient with SVT becomes hypotensive and confused. What is the priority intervention?
Repeat vagal maneuvers
Administer adenosine
Synchronized cardioversion
Observation only
Why is synchronized cardioversion used instead of defibrillation for unstable SVT?
It delivers lower energy
It avoids shocking during the T wave
It works only on ventricular rhythms
It eliminates the need for sedation
Which rhythm characteristic supports SVT rather than atrial fibrillation?
Irregular rhythm
Absence of P waves
Regular ventricular response
Loss of atrial kick
Which long-term treatment may be considered for recurrent SVT?
Permanent pacemaker
Anticoagulation therapy
Catheter ablation
MAZE procedure
Which patient is at highest risk for developing SVT?
Older adult with hypertension
Young adult consuming excessive caffeine
Patient with hypothermia
Patient with complete heart block
Which symptom is most commonly reported during SVT episodes?
Sudden chest trauma
Lightheadedness or dizziness
Hemoptysis
Bradycardia
Which statement best summarizes SVT management?
Always treat immediately with defibrillation
Treat based on stability: vagal → adenosine → cardioversion
Observation only is sufficient
Pacemaker insertion is first-line therapy
Which ECG findings are characteristic of atrial fibrillation? Select all that apply.
Irregularly irregular rhythm
Absence of identifiable P waves
PR interval measurable
Fibrillatory baseline
Variable ventricular rate
A patient's ECG shows AFib with a ventricular rate of 88 bpm. How should this rhythm be documented?
AFib with RVR
Controlled AFib
Sinus tachycardia
Atrial flutter
Which ventricular rate is considered AFib with rapid ventricular response (RVR)?
78 bpm
96 bpm
112 bpm
148 bpm
Why is the PR interval not measurable in atrial fibrillation?
AV node is blocked
P waves are absent due to chaotic atrial activity
Ventricles are pacing the heart
QRS complexes are widened
Which assessment finding is a classic clinical clue for atrial fibrillation?
Equal apical and radial pulses
Apical pulse faster than radial pulse
Bradycardia
Bounding peripheral pulses
What is the primary hemodynamic consequence of atrial fibrillation?
Increased preload
Loss of atrial kick and decreased cardiac output
Increased ventricular filling time
Improved coronary perfusion
Which conditions are commonly associated with the development of AFib? Select all that apply.
Hypertension
Heart failure
Coronary artery disease
Hypothermia
Post–cardiac surgery
Why are patients with atrial fibrillation at high risk for stroke?
Increased ventricular contraction
Blood stasis in the atria leading to thrombus formation
Increased platelet production
Narrow QRS complexes
Which nursing action is most important when caring for a patient newly diagnosed with AFib?
Prepare for immediate pacemaker insertion
Assess for signs of decreased cardiac output
Assess need for anticoagulation therapy
Restrict all activity
Which medications are commonly used to control ventricular rate in AFib? Select all that apply.
Beta blockers
Calcium channel blockers
Digoxin
Adenosine
Epinephrine
Which medication is used primarily to prevent stroke in atrial fibrillation?
Metoprolol
Diltiazem
Warfarin
Adenosine
A patient with AFib asks why anticoagulation is needed. Which explanation is best?
It lowers your heart rate.
It prevents clot formation that can cause a stroke.
It converts the rhythm back to normal.
It strengthens heart contractions.
Which patient with AFib is the best candidate for synchronized cardioversion?
AFib for unknown duration without anticoagulation
AFib with controlled rate and no symptoms
New-onset AFib with hemodynamic instability
Chronic AFib on long-term anticoagulation
Why is cardioversion often delayed in atrial fibrillation?
Risk of ventricular fibrillation
Risk of thrombus dislodgement and stroke
Cardioversion is ineffective in AFib
Sedation is contraindicated
Which AFib classification describes episodes that start and stop spontaneously, usually lasting less than 7 days?
Persistent
Permanent
Paroxysmal
Chronic
Which statement is true regarding permanent atrial fibrillation?
Cardioversion is always effective
Rhythm control strategies are no longer attempted
Anticoagulation is unnecessary
Pacemaker insertion is mandatory
Which procedure creates scar tissue in the atria to block abnormal electrical pathways?
Pacemaker insertion
Catheter ablation
Defibrillation
PCI
Why may atrial flutter respond better to cardioversion than atrial fibrillation?
Flutter has chaotic atrial activity
Flutter has a more organized re-entry circuit
Flutter occurs in the ventricles
Flutter has lower stroke risk
Which ECG pattern is most consistent with atrial flutter rather than AFib?
Irregular baseline
Sawtooth atrial waves
Absent atrial activity
Random ventricular response
Which statement best summarizes atrial fibrillation priorities?
Rhythm conversion is always the first goal
Stroke prevention and rate control are key priorities
Defibrillation is first-line therapy
Pacemaker insertion is curative
Which ECG findings are characteristic of atrial flutter? Select all that apply.
Atrial rate 200–350 bpm
Sawtooth flutter waves
Irregularly irregular rhythm
Ventricular rate depends on conduction ratio
Organized atrial activity
Compared to atrial fibrillation, atrial flutter has which characteristic?
More chaotic atrial activity
More organized re-entry rhythm
Always slower ventricular response
No risk of stroke
Which rhythm feature helps distinguish atrial flutter from AFib?
Absence of P waves
Irregular ventricular rhythm
Sawtooth pattern on ECG
Narrow QRS complexes
Why does atrial flutter often respond better to cardioversion than AFib?
Flutter originates in the ventricles
Flutter has a single organized circuit
Flutter has no thrombus risk
Flutter causes less atrial contraction
Which ventricular rates may be seen in atrial flutter?
Always below 100 bpm
Fixed at 150 bpm
Variable based on AV conduction ratio
Always irregular
Which complication is atrial flutter patients at risk for?
Ventricular standstill
Stroke
Asystole only
Complete heart block
Which treatment goals are appropriate for atrial flutter? Select all that apply.
Rate control
Rhythm conversion
Stroke prevention
Permanent pacing
Defibrillation as first-line
Which medication classes are used for rate control in atrial flutter? Select all that apply.
Beta blockers
Calcium channel blockers
Digoxin
Adenosine
Epinephrine
A patient with atrial flutter becomes hypotensive and confused. What is the priority intervention?
Vagal maneuvers
Adenosine
Synchronized cardioversion
Observation
Which statement best summarizes atrial flutter?
Always benign
No organized atrial activity
Regular atrial rhythm with sawtooth waves
No risk for thrombus
Which ECG findings are characteristic of PVCs? Select all that apply.
Premature beat
Wide QRS complex (>0.12 sec)
T wave opposite direction of QRS
P wave before every QRS
Compensatory pause
PVCs originate from which location?
SA node
AV node
Atrial ectopic focus
Ventricular ectopic focus
Which statement about PVCs is accurate?
They occur only in diseased hearts
They are the most common dysrhythmia
They always require treatment
They are always life-threatening
Which factors can trigger PVCs? Select all that apply.
Stress
Caffeine
Hypoxia
Electrolyte imbalance
Complete heart block
Why may a patient not feel a pulse with every PVC?
PVCs always cause ventricular fibrillation
Ventricles contract too early for adequate filling
Atria stop contracting
SA node is suppressed
Which PVC pattern is most concerning?
Occasional isolated PVCs
PVCs at rest only
Runs of PVCs (>3 in a row)
PVCs that disappear with activity
A nurse giving report is asked about PVC frequency. Why is this important?
PVCs indicate atrial fibrillation
Increasing PVCs may precede VT or VF
PVCs are normal and not documented
PVCs require immediate pacing
Which underlying condition increases the risk of PVCs becoming dangerous?
Hypertension alone
Decreased ejection fraction
Young age
Athletic conditioning
What is the priority nursing action when frequent PVCs are observed?
Immediate cardioversion
Assess oxygenation and electrolytes
Administer adenosine
Begin CPR
Which statement best summarizes PVC management?
Treat all PVCs aggressively
Ignore PVCs entirely
Treat the underlying cause and monitor rhythm
Insert a pacemaker immediately
