Download Nursing 259 - University of Hawaii

Basic EKG Interpretation
Atrial Arrhythmias
Atrial Arrhythmias
Premature Atrial Contractions
Atrial Tachycardia
Paroxysmal
NonParoxysmal
Atrial Flutter
Atrial Fibrillation
Wandering Atrial Pacemaker
Multifocal Atrial Tachycardia
Premature Atrial Contraction
(PAC)
Caused by enhanced automaticity
Occurs in addition to underlying rhythm
P wave of PAC
Occurs early
Different looking
May have different PR interval
QRS of PAC
May be blocked or nonconducted – ventricle is still
refractory
Can be normal or wide in duration
Effects of PAC
May cause palpitations
May be precursor to worse arrhythmias
– such as atrial flutter or fibrillation
May decrease cardiac output – occurs
soon after previous beat, not enough
time for ventricle to fill up again
Premature Atrial Contraction
(5th beat)
Premature Atrial Contraction
(5th beat)
Blocked PAC
Enlarged Photo
PAC’s
Common causes
Emotions
Caffeine
Sympathomimetic drugs
ischemia
Treatment of PAC
Usually none
Eliminate cause
PAC: Nursing Implications
Monitor serum potassium levels
Monitor serum digoxin levels
Monitor for CHF
Eliminate causes
Monitor for more arrhythmias
Atrial Tachycardia
Rapid Atrial Arrhythmia
Paroxysmal: Starts and stops suddenly
Usually caused by reentry
Usually initiated by PAC
Nonparoxysmal: Sustained
Usually caused by enhanced automaticity
Supraventricular Tachycardia (SVT): Generic
term when P waves can’t be seen
Atrial Tachycardia
P wave: Regular and upright, may be
buried in preceding T wave; may be
initiated by PAC
Rate: 160 - 220 beats/minute
Rhythm: Regular
QRS: May be less than P waves
because of block; may be normal or
wide in duration
Causes of Atrial Tachycardia
Stress
Excessive use of stimulants
Accessory conduction pathway
Chronic lung disease
Digoxin toxicity (particularly atrial tach
with block)
Effects of Atrial Tachycardia
May decrease cardiac output –
tachycardia causes less time in diastole
Decreased coronary perfusion coronary arteries get less blow flow as
less time in diastole
Chest pain – due to decreased coronary
perfusion
Atrial Tachycardia
Atrial Tach with Block
Non-Paroxysmal Atrial
Tachycardia
PAT
Treatment of Atrial
Tachycardia
Vagal stimulation
Carotid sinus massage
Valsalva maneuver
Diving reflex
Synchronized cardioversion
Overdrive pacing
Adenosine IV: 6 mg rapidly, may give
12 mg in 1 -2 minutes
Treatment of Atrial
Tachycardia
Diltiazem: 0.25 mg/kg bolus; then 10
mg/hr
Digoxin IV except if arrhythmia is due
to accessory conduction pathway or
digoxin toxicity
Amiodarone
Beta-blockers
Atenolol, metoprolol, esmolol
Nursing Implications - Atrial
Tachycardia
Check for clues as to cause
Monitor digoxin level
Have resuscitative equipment available
Supplemental oxygen
Assess for chest pain and CHF
Atrial Flutter
Usually a transient rhythm
Usually precedes atrial fibrillation
Results either from reentry or enhanced
automaticity
Seen in people with ischemic heart or
valvular disease
Atrial Flutter
Flutter waves: sawtooth pattern
Atrial rate: 250-350 beats/minute
Atrial rhythm: regular, may be buried in QRS
complex
PR interval: not measurable
QRS: may appear distorted
QRS rate: described in terms of ratio of F
waves to QRS (4:1, 2:1)
QRS rhythm: may be regular or irregular
Atrial Flutter
Atrial Flutter
Atrial Flutter
Atrial Flutter
Effects
Loss of Atrial Kick (delay of the impulse at the AV
node so that the atria can contract to increase
ventricular filling and cardiac output)
Decreased cardiac output
Treatments
Amiodarone, procainamide, beta-blockers, digoxin,
calcium channel blockers
Cardioversion very effective
Ibutilide (Corvert) - chemical cardioverter: 1
mg/50 D5W over 10 min; may repeat in 10 min
Nursing Implications: Atrial
Flutter
Ensure adequate oxygenation
For cardioversion: need informed
consent, if elective, sedation and
resuscitative equipment
Atrial Fibrillation
Due to enhanced automaticity
Usually chronic rhythm
Associated with:
Ischemic heart disease
Valvular disease
Chronic lung disease
Post cardiac surgery
Hypokalemia
Atrial Fibrillation
Fibrillatory waves: wavy baseline
Atrial rate: over 350 beats/minute
Atrial rhythm: irregular
PR interval: not measurable
QRS: usually normal and alike
QRS rate: may vary
controlled: less than 100 beats/minute
uncontrolled: over 100 beats/minute
QRS rhythm: irregularly irregular
Atrial Fibrillation
Atrial Fibrillation
Atrial Fibrillation
Atrial Fibrillation
Effects:
Loss of atrial kick
May cause mural thrombi – thrombi on
endocardial wall due to stagnant blood flow
Treatment:
Same as for atrial flutter
Anticoagulate if over 48 hours duration
Goal for chronic arrhythmia is to control
ventricular rate
Cardioversion less effective, if chronic – usually
delayed if greater than 48 hours duration until
anticoagulated and atrial thrombi excluded
Atrial Fibrillation: Nursing
Implications
Consider this arrhythmia in irregular
pulse with pulse deficit
Monitor for CHF
High risk for CVA
Consider hyperthyroidism, alcoholic
cardiomyopathy – may cause atrial
fibrillation
Wandering Atrial Pacemaker
Due to several atrial and AV ectopic
sites
Associated with:
Rheumatic heart disease
Vagal stimulation
Digoxin toxicity
Usually no effects on client
Wandering Atrial Pacemaker
P waves: At least three different looking P
waves. Some may be inverted
PR interval varies
QRS:
Usually normal and alike
Rate usually 60 - 100 beats/minute
Rhythm usually irregular
In rates greater than 100: Multifocal Atrial
Tachycardia (MAT)
Wandering Atrial Pacemaker
MAT
Wandering Atrial Pacemaker
Treatment:
Usually none except if digoxin toxicity
Coughing may help if due to vagal stimulation
Treatment usually ineffective for MAT
Nursing Implications:
Monitor serum digoxin levels
Monitor for bradycardia
Monitor for hypotension