View source for Premature atrial contraction

==Background==
Premature atrial contractions (PACs) are common and typically benign premature beats characterized by an abnormal early P wave within a cardiac cycle. Less commonly, they can precipitate [[atrial fibrillation]], [[atrial flutter]], or [[SVT]].<ref>Specific dysryhthmias. In: Marx K, Rosen P, ed. Rosen's Emergency Medicine: Concepts and Clinical Practice. 8th ed. Philadelphia, PA: Elsevier/Saunders, 2014.</ref>

==Clinical Features==
*Palpitations
*Shortness of breath
*Anxiety
*Asymptomatic

==Differential Diagnosis==
{{Palpitations DDX}}

==Evaluation==
*Obtain EKG and look for: 
**P waves that appear sooner than expected sinus beat
**Ectopic P waves that have different morphology
**Interval between normal P waves encompassing the PAC is less than twice the existing P-P cycle length (noncompensatory pause)<ref>Brady W, Laughrey T, Ghaemmaghami C. Cardiac rhythm disturbances. In Tintinalli's Emergency Medicine: A Comprehensive Guide. Tintinalli J, et al. ed. 8th ed. McGraw Hill. New York, NY, 2016.</ref>
[[File:PAC.png|frame|EKG showing PACs]]
*Rule out underlying conditions:
**Chronic heart disease (increases prevalence of PACs)
**Chronic lung disease (increases prevalence of PACs)
**Drugs: cocaine, amphetamines, caffeine, nicotine, digoxin

==Management==
*No specific treatment necessary
*If symptomatic, treat underlying disorder or discontinue offending agent.

==Disposition==
*Discharge home, no specific follow-up (unless identifiable underlying etiology that needs to be treated).

==See Also==
*[[Palpitations]]
*[[Premature ventricular contraction]]
*[[Premature junctional contraction]]

==External Links==


==References==
<references/>

[[Category:Cardiology]]