ACLS Rhythms Cheat Sheet

Amanda Hooper2008-2009

Normal Sinus Rhythm

Arrest Rhythms

AsystolePEA

Vfib/pulseless Vtach

Agonal Rhythm/Asystole

Pulseless Electrical Activity (PEA)

Note that PEA can look like any rhythm (any organized electrical activity), but if no pulse it is PEA

Course Ventricular Fibrillation

Fine Ventricular Fibrillation

Non-Arrest Rhythms

• One very important thing that seems like it should be easy but I always have to remember how to do: determine the rate…

• Find a QRS complex that is closest to a dark vertical line. Then count the number of “big boxes” until the next QRS complex. For each “big box” you pass, select the next number off the mnemonic "300-150-100-75-60-50" to estimate the rate.

• Alternatively, you can count the number of big boxes between two QRS complexes and divide 300 by that number.

Sinus Tachycardia

Note the rate is > 100 bpm

Atrial Fibrillation

Note it is “irregularly irregular” and there are no definite p waves

Atrial flutter

Note the “saw-tooth” pattern

Reentry Supraventricular Tachycardia

This is a regular, narrow complex tachycardia without P waves, usually with a sudden

onset and cessation

Monomorphic Ventricular Tachycardia

With ventricular rhythms, QRS is usually wide. V tach is more organized electrical activity than v fib, but v tach

often deteriorates into v fib so both are very bad!

Polymorphic Ventricular Tachycardia

Torsades de Pointes

A special type of polymorphic Vtach-Note the “spindling” in the QRS complexes

Sinus Bradycardia

Note the rate <60 bpm. Could be physiologic or symptomatic depending on the patient.

1st Degree AV Block

Note the increased PR interval

2nd Degree AV Block: Mobitz type I (Wenckebach)

Note the progressive lengthening of the PR interval until one P wave (arrow) is not followed by a QRS

2nd Degree Block: Mobitz type II

Note the regular PR interval until beats are dropped.

3rd Degree AV Block

Note the regular P waves and regular ventricular “escape beats” but no relationship between the P waves and

escape beats.