Whether this is the result of multiple variable Wenckebach conduction ratios out of different AV nodal levels, or simply random conduction ( from concealed conduction) of flutter impulses through the AV node is uncertain. On occasion - AFlutter may conduct with a truly variable ventricular response.

Odd conduction ratios ( 1:1 3:1, etc.) are rare with AFlutter ( especially if the patient is not on medication and does not have WPW).

This is thought to be due to Wenckebach conduction of flutter impulses out of two or more levels within the AV node.

Variable conduction ratios ( usually alternating at fixed intervals, such as 2:1 3:2, etc.) are not uncommon with AFlutter.

4:1 AV conduction is the next-most-common ventricular response to AFlutter. At the typical AFlutter rate of ~300/minute - this results in a regular ventricular response that is often quite close to 150/minute.

The most common ventricular response to untreated AFlutter is 2:1 AV conduction.

Longterm anticoagulation is advised for both rhythms - but the risk of thromboemblism appears to be much greater for chronic AFib, given the much more disorganized nature of that rhythm. Similar medications are used for both rhythms for initial treatment - but it may be more difficult to control the ventricular response to AFlutter than to AFib. While both AFib and AFlutter are increasingly susceptible to ablation as an effective treatment modality - AFlutter clearly responds better than AFib to ablation.

Clinically, distinction between AFib vs AFlutter is important for several reasons.

Such rhythms are sometimes designated as, “AFib-Flutter” as a descriptive term to indicate that while the rhythm looks a lot like AFlutter on ECG - it “behaves” clinically as Fib. A-fib and a-flutter are very common dysrhythmias among patients. As a nurse taking care of patients you will have to know the basics about these type of atrial dysrhythmia. Although superficially regular and sawtooth in pattern - such waveforms on closer inspection are not regular. This EKG dysrhythmia practice quiz will test your knowledge on the difference between atrial fibrillation and atrial flutter, also called a-fib and a-flutter. Flutter waves are typically best seen in leads II, III aVF, V1, V2 and V3.

At times, AFib may “organize” ( at least partially, usually within the right atrium) - such that waveforms resembling flutter are seen in lead V1, but not in other leads. The flutter waves (on the contrary to f-waves in atrial fibrillation) have identical morphology (in each ECG lead). Distinction between AFib vs AFlutter is not always clear-cut when the ventricular response is not regular.In this case - I believe atrial activity IS regular enough (t here is no more than very minimal P-P variation, seen for some cycles in V1) - at a typical enough rate close to 300/minute ( ~280/minute in this tracing) - that I’d diagnose this exactly as Dawn did = AFlutter with a Variable Ventricular Response.

Afib vs a flutter on ecg