<unk><unk><unk>  may have a variety of manifestations on the electrocardiogram.  The diagnosis of an PACs is made when a P wave with a morphology different from that of the sinus P wave (inverted or biphasic) occurs earlier than the anticipated sinus P wave.  It is always advisory to examine each lead as subtle differences in morphology may be present.
Premature atrial contraction electrocardiogram
Premature ventricular contraction electrocardiogram
Intraventricular conduction delay electrocardiogram
Junctional bradycardia electrocardiogram
Pulseless ventricular tachycardia electrocardiogram
Ventricular fibrillation electrocardiogram
Atrial flutter electrocardiogram
Junctional tachycardia electrocardiogram