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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).
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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
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
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 • 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 • 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 • 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