Rate

160-240

Regularity

Regular

P waves

Hidden in previous T wave

PRI

Unidentifiable

QRS

0.08-0.12

 
Rate

Any

Regularity

Regularly Irregular

P waves

Upright and uniform

PRI

Gradually lengthening until dropped

QRS

0.08-0.12

 
Rate

< 40

Regularity

Regular

P waves

None

PRI

None

QRS

> 0.12; bizarre