Premature Atrial Complex | Reference Guide
EKG FeaturesRate: Usually normal but depends on underlying rhythm
P Wave: Premature, positive and shape is abnormal
PR Interval: Normal or longer
QRS: 0.10 sec or less
This early impulse causes an early cardiac complex which disrupts the underlying rhythm.
Premature atrial contractions are a common arrhythmia with early beats. PACs are caused by ectopic atrial sites firing an electrical signal before the next normal SA node fires. PACs can occur in healthy young and elderly patients. Premature atrial contractions are also called premature atrial complexes.
External Source: http://www.medicinenet.com/heart_rhythm_disorders/page2.htm
EKG Tracing Example
Authors and ReviewersAuthored by Thomas O'Brien
Medically reviewed by Dr. Jonathan Keroes, MD
Last Update: 11/8/2021