Premature Atrial Contractions
PAC stands for Premature Atrial Contraction, which is an early electrical impulse originating from the atria (the upper chambers of the heart). PACs are a type of arrhythmia where the heart beats prematurely due to an extra, abnormal electrical signal. This results in a heart rhythm that feels irregular.
ECG Features
Heart rate: heart rate varies
P wave: visible
PR-interval: normal
QRS: narrow
Rhythm: regular except PAC beat
PACs often occur in repeating patterns:
Example:1
