Wandering Atrial Pacemaker (WAP) / MAT

• Rhythms originating in the atria are characterized by several criteria
• Matching upright P waves and an atrial rate (heart rate of the P waves) exceeding 160 at rest
• Absence of P waves, indicated by a wavy or sawtooth baseline between QRS complexes
• Presence of P waves with three or more distinct shapes
• Interruption of another rhythm by a premature abnormal P wave, with or without a QRS complex
• Heart rate of 130 or higher, regular rhythm, and P waves that are not discernible or may be present

Wandering Atrial Pacemaker (WAP) / Multifocal Atrial Tachycardia (MAT)

• WAP has a rate of under 100, while MAT exceeds 100
• Irregular rhythm
• 3 or more different shapes of P waves, sometimes with no P waves at all
• Variable PR intervals, and QRS under 0.12s
• WAP is caused by medication side effects, hypoxia, vagal stimulation, or myocardial infarction (MI)
• MAT is caused by chronic obstructive pulmonary disease (COPD) or heart disease
• WAP typically has no adverse effects
• MAT can show signs of decreased cardiac output (CO) if the heart rate is too fast
• WAP does not require treatment
• MAT can be treated with beta-blockers or calcium channel blockers if CO is decreased

Premature Atrial Complexes (PACs)

• Irregular rhythm that are interrupted at any rate
• P waves shaped differently from sinus P waves, potentially hidden in T waves
• PR interval between 0.12-0.20s, and QRS under 0.12
• Hyper atria fire early, before the next beat
• Medications, stimulants, caffeine, bronchodilators, tobacco, hypoxia, or heart disease can cause this
• Frequent PACs can be an early sign of heart issues, atrial tachycardia, or fibrillation
• Occasional PACS have no ill effects
• Treatment is not typically needed, but stimulants such as caffeine and tobacco should be omitted.

Paroxysmal Atrial Tachycardia (PAT)

• 160-250 beats per minute on the atrial tachycardia, the rhythm it will interrupt will have a different rate
• Regular but interrupted beat
• Shaped the same in atrial tachycardia, but different from sinus P wave
• PR interval range of 0.12 - 0.20s, constant, and QRS complex less than 0.12s
• Same cause as PACs or Sinus Tachycardia
• Prolonged causes decreased cardiac output
• Treat with digitalis, calcium channel blockers, beta-blockers, sedation, amiodarone, adenosine, and O2
• Elective cardioversion may be needed

Atrial Flutter

• Rate between 250-350
• Regular if the conduction ratio is constant; irregular if the conduction ratio varies
• No P waves present
• Sawtooth shaped waves between QRS complexes
• PR interval not measured
• QRS complex less than 0.12s
• Almost always implies heart disease, pulmonary embolism, valvular heart disease, thyroid storm, and lung disease
• Decreased cardiac output
• Treat with Digitalis, Calcium Channel Blockers, beta blockers, adenosine, carotid sinus massage, cardioversion

Atrial Fibrillation

• Rate between 350-700
• Irregular, completely unpredictable
• No P waves
• No PR interval
• QRS complex less than 0.12s
• MI, lung disease, valvular heart disease, and hyperthyroidism can cause this
• Drop in CO
• Can result in MI, strokes or blood clots in the lung
• Depends on duration of Afib
• In pts with Afib greater then 48 hrs, begin anticoagulants and delay cardioversion

Supraventricular Tachycardia (SVT)

• Rate of 130 or higher
• Regular beat
• Not discernible
• PR cannot be measured
• SAME as PAT
• Decreased CO
• Treat with adenosine and digitalis
• QRS measures less than 0.12s, secondary to rapid HR and can use ibutilide, Calcium channel blockers, beta blockers to treat

Wandering Atrial Pacemaker (WAP) and Multifocal Atrial Tachycardia (MAT) are rhythms originating in the atria. WAP has a rate of under 100, while MAT exceeds 100. Both have irregular rhythms and variable PR intervals.