NCLEX EKGs*

Sinus bradycardia strip

Sinus bradycardia characteristics

Conduction pathway is the same as in normal sinus, but heart rate <60

Sinus bradycardia clinical associations

-Athletes
-Sleep
-Carotid sinus massage
-Valsalva maneuver or vagal stimulation
-Hypothermia
-Increased intraocular pressure
-Certain drugs (beta blockers, Ca2+ channel blockers)
-Hypothyroidism, increased ICP, hypoglycemia, MI

Sinus bradycardia symptoms

-Pale, cool skin
-Hypotension
-Weakness
-Angina
-Dizziness/syncope
-Confusion/disorientation
-SOB

Sinus bradycardia treatment

If patient is symptomatic:
-Atropine
-Transcutaneous pacing
-Dopamine or epinephrine
-Permanent pacemaker

Sinus tachycardia strip

Sinus tachycardia description

Conduction pathway is the same as in normal sinus, but heart rate is >100

Sinus tachycardia clinical associations

-Stressors (exercise, fever, pain, hypotension, hypovolemia, anemia, hypoxia, hypoglycemia, myocardial ischemia, HF, hyperthyroidism, anxiety, fear)
-Drugs (epinephrine, norepinephrine, atropine, caffeine, theophylline, hydralazine, Sudafed)

Sinus tachycardia symptoms

-Dizziness
-Dyspnea
-Hypotension
-Angina

Sinus tachycardia treatment

Treat underlying cause:
-Pain management
-Vagal maneuvers
-Beta blockers (metoprolol, adenosine); Ca2+ channel blockers (diltiazem)
-Synchronized cardioversion if clinically unstable

Atrial flutter strip

Atrial flutter description

Characterized by recurring, regular sawtooth, flutter waves
-Atrial rate 200-350

Atrial flutter clinical associations

Rarely occurs in healthy heart
-CAD, hypertension, mitral valve disorders, pulmonary embolus, chronic lung disease, cor pulmonale, cardiomyopathy, hyperthyroidism
-Use of drugs (digoxin, quinidine, epinephrine)

Atrial flutter symptoms

Decreased CO can cause HF
*Increased risk of STROKE! (risk of thrombus formation in the atria from stasis of blood; give warfarin to prevent stroke in these patients)

Atrial flutter treatment

Goal: slow ventricular response by increasing AV block
-Ca2+ channel blockers, beta blockers
-Electrical cardioversion in an emergency
-Antidysrhythmia drugs (ibutilide, amiodarone, flecainide, dronedarone)
*Radiofrequency catheter ablation is the treatme

Atrial fibrillation strip

Atrial fibrillation description

Disorganization of atrial electrical activity bc of multiple ectopic foci --> loss of effective atrial contraction
-Atrial rate 350-600
-P waves replaced by chaotic, fibrillatory waves
-Ventricular rate is usually irregular
CONTROLLED A FIB: ventricular r

Atrial fibrillation clinical associations

-CAD, valvular heart disease, cardiomyopathy, hypertensive heart disease, HF, pericarditis
-Acutely w/ thyrotoxicosis, alcohol intoxication, caffeine use, electrolyte disturbances, stress, heart surgery

Atrial fibrillation symptoms

Decrease in CO bc ineffective atrial contractions
*Clots develop bc of blood stasis
STROKES! So warfarin.

Atrial fibrillation treatment

Goal: decrease ventricular response to <100, prevent stroke, and convert to sinus rhythm
-Ca2+ channel blockers (diltiazem); Beta blockers (metoprolol); dronedarone; digoxin
-Antidysrhythmia drugs (amiodarone, ibutilide)
-Electrical cardioversion
-Radiofr

First-degree AV block strip

Brackets indicate prolonged PR interval

First-degree AV block description

Impulse is conducted to ventricles, but time of AV conduction is prolonged. After movement through AV node, ventricles respond normally.
-HR normal, rhythm regular; P wave normal
-PR interval prolonged

First-degree AV block clinical associations

-MI, CAD, rheumatic fever, hyperthyroidism, electrolyte imbalances, vagal stimulation
-Drugs (digoxin, beta blockers, Ca2+ channel blockers, flecainide)

First-degree AV block symptoms

Asymptomatic
-Usually not serious, but can be a sign of higher degrees of AV block

First-degree AV block treatment

No treatment
Monitor patients for more changes in heart rhythm

Third-degree AV block strip

Third-degree AV block description

AKA complete heart block
No impulses from the atria are conducted to the ventricles
Atrial and ventricular rhythms are regular but are unrelated to each other
No relationship between the P wave and the QRS complex

Third-degree AV block clinical associations

-Severe heart disease: CAD, MI, myocarditis, cardiomyopathy
-Amyloidosis, progressive systemic sclerosis
-Digoxin, beta blockers, Ca2+ channel blockers

Third-degree AV block symptoms

Reduced CO with subsequent ischemia, HF, and shock
-Syncope (resulting from severe bradycardia or periods of asystole)

Third-degree AV block treatment

If symptomatic:
-Transcutaneous pacemaker until a temporary transvenous pacemaker can be inserted
-Atropine, dopamine, epinephrine temporarily until pacing is started
-Patient will need a permanent pacemaker ASAP

Premature ventricular contractions (PVC) strip

Premature ventricular contractions (PVC) description

Contraction coming from an ectopic focus in the ventricles; early QRS complex
-Wide and distorted in shape compared to normal QRS
-V tach occurs when there are 3 or more consecutive PVCs

Premature ventricular contractions (PVC) clinical association

-Stimulants (caffeine, alcohol, nicotine, aminophylline, epinephrine, isoproterenol, digoxin)
-Electrolyte imbalances, hypoxia, fever, exercise, emotional stress
-MI, mitral valve prolapse, HF, CAD

Premature ventricular contractions (PVC) symptoms

Usually not harmful in patient with a normal heart
In heart disease, may reduce CO and lead to angina and HF
-Obtain patient's apical-radial pulse rate (PVCs don't generate a peripheral pulse, this causes pulse deficit)

Premature ventricular contractions (PVC) treatment

Relates to cause
-Assess pt's hemodynamic status to determine if drug tx is needed
-Beta blockers, procainamide, amiodarone

Ventricular tachycardia (VT) strip

Ventricular tachycardia (VT) description

A run of three or more PVCs
Life threatening dysrhythmia because of decreased CO and possibility of developing VF (lethal)
-Ventricular rate 150-250
-Stable (patient has a pulse) or unstable (patient is pulseless)

Ventricular tachycardia (VT) clinical associations

-MI, CAD, significant electrolyte imbalances, cardiomyopathy, mitral valve prolapse, long QT syndrome, drug toxicity, CNS disorders
-Can be seen in patients who have no evidence of cardiac disease

Ventricular tachycardia (VT) symptoms

Severe decrease in CO causes:
-Hypotension, pulmonary edema, decreased cerebral blood flow, cardiopulmonary arrest
-Must be treated quickly, even if occurs briefly
-VF may develop

Ventricular tachycardia (VT) treatment

Precipitating causes must be identified and treated
If patient is clinically stable (has a pulse):
-IV procainamide, sotalol, amiodarone
-IV magnesium, isoproterenol, phenytoin
-Antitachycardia pacing
-Cardioversion
If pulse is absent: Treated as VF:
-CPR

Ventricular fibrillation (VF) strip

Ventricular fibrillation (VF) description

Irregular waveforms of varying shapes and amplitude
Firing of multiple ectopic foci in the ventricle (ventricle is "quivering")
-No CO occurs
-Lethal

Ventricular fibrillation (VF) clinical associations

-MI, myocardial ischemia
-HF, cardiomyopathy
-May occur during cardiac pacing or cardiac cath procedures bc of catheter stimulation of ventricle
-Coronary reperfusion after thrombolytic therapy
-Electric shock, hyperkalemia, hypoxemia, acidosis, drug toxi

Ventricular fibrillation (VF) symptoms

Unresponsive, pulseless, and apneic state
Treat rapidly

Ventricular fibrillation (VF) treatment

Immediate CPR and ACLS w/ defibrillation and drug tx
-Epinephrine, vasopressin
-No delay in using defibrillator once available

Asystole description

Total absence of ventricular electrical activity
-Occasionally P waves are seen
-Depolarization doesn't occur
-Patient is pulseless, unresponsive, apneic

Asystole clinical associations

-Advanced cardiac disease
-Severe cardiac conduction system disturbance
-End-stage HF

Asystole treatment

-CPR with ACLS
-Epinephrine, vasopressin, intubation
-Not a shockable rhythm

Pulseless electrical activity (PEA) description

Electrical activity seen on ECG, but no mechanical activity of ventricles
-Patient has no pulse

Pulseless electrical activity (PEA) clinical associations

H's and T's

Pulseless electrical activity (PEA) treatment

-CPR
-Epinephrine, intubation
-Correct underlying cause (H's and T's)
-Not a shockable rhythm

5 H's

-Hypovolemia
-Hypoxia
-Acidosis (hydrogen ion)
-Hyper/hypokalemia
-Hypothermia

5 T's

-Toxins
-Tamponade (cardiac)
-Tension pneumothorax
-Thrombosis (heart; acute, MI)
-Thrombosis (lungs; PE)

Conduction pathway

SA node --> atrial contraction --> AV node --> bundle of His --> L&R bundle branches --> Purkinje fibers --> ventricles

P wave

Atrial depolarization (contraction)

PR interval

Time taken for impulse to travel through atria --> AV node --> bundle of His --> bundle branches --> Purkinje fibers

QRS complex

Depolarization (contraction) of both ventricles (systole)

ST segment

Time between ventricular depolarization (contraction, systole) and repolarization (diastole)

T wave

Ventricular repolarization (diastole)

QT interval

Time taken for entire depolarization (contraction, systole) and repolarization (diastole) of the ventricles

STEMI

NSTEMI

NSR

ST

SB

A flutter

A fib

SVT

PVC

type of premature contraction

1st degree of AVB

2nd degree AVB type 1

2nd degree AVB type 2

3rd degree of AVB

NSR

P: Upright one for every QRS
PR: 0.12-0.20
QRS:Less than 0.12
RATE: 60-100 BPM
RHYTHM: Regular

Sinus Bradycardia

P:Upright one for every QRS
PR: 0.12-0.20
QRS: Less than 0.12
RATE: Less than 60 BPM
RHYTHM: Regular

Sinus Tachycardia

P: Upright one for every QRS
PR: 0.12-0.20
QRS: Less than 0.12
RATE: Greater than 100 BPM
RHYTHM: Regular

Sinus Arrhythmia

P: Upright one for every QRS
PR: 0.12-0.20
QRS: Less than 0.12
RATE: 60-100 BPM (can be slower or faster)
RHYTHM: Regularly Irregular

Atrial Fibrillation

P: None, fibrillatory waves
PR: None
QRS: Less than 0.12
RATE: 60-100 BPM
RHYTHM: Irregularly Irregular

AF-RVR

P: None, fibrillary waves
PR: None
QRS: Less than 0.12
RATE: Greater than 100 BPM
RHYTHM: Irregularly Irregular

Atrial Flutter

P: None, flutter waves
PR: None
QRS: Less than 0.12
RATE: Usually 60-100 often seen at 130, 150-160
RHYTHM: Regular (Irregular with variable conduction)

SVT

P: May be hard to find. If present, one for every QRS complex
PR: Usually not measurable
QRS: Less than 0.12
RATE: 150-240 BPM
RHYTHM: Regular

Asystole

P: None
PR: None
QRS: None
RATE: None
RHYTHM: None

First Degree Heart Block

P: One for every QRS
PR: Greater than 0.20

Second Degree Type 1 (Mobitz 1, Wenckebach)

P: One for every QRS
PR: Elongates, eventually QRS is lost
QRS: Usually less than 0.12, can be wider
RATE: Usually 60-100 BPM, can be slower
RHYTHM: Regular

Second Degree Type 2 (Mobitz 2)

P: 2 or more for every QRS
PR: Constant
QRS: Usually less than 0.12, can be wider
RATE: Usually 60-100, can be slower
RHYTHM: Usually regular

Third Degree Heart Block

P: One or more for every QRS
PR: Absent
QRS: Usually less than 0.12, can be greater
RATE: 60-100 BPM, can be slower
RHYTHM: Regular