1 - Rate: fast and slow and slow and fast unpredictably

2 - Rhythm:
- P is before each QRS. QRS is after each P.
- Q is normal looking
- Irregular: there's like a pause between some beat

3 - Axis: skip this for now

4 - Width:
- PR interval width is normal (5ss at all beats) and fixed (Remember sinus rhythm has fixed and normal PR interval)
- Q width is normal (<3ss)
- RR: 1/2RR width is less than QT segment= normal

5 - Height:
- No ST elevation
- Upright P wave in lead II (Remember sinus rhythm has upright P wave in lead II)

6 - Pts symptoms:
- Usually EKG sinus arrythmias will have rhythms change as pt breathing in and breathing out
- Usually older pt with syncope, fatigue and worsening HF may have sinus arrhythmias or sinus bradycardia NOT owing to use of beta blocker, that would mean pt may need a pacemaker (sick sinus syndrome)