What are the criteria for atrial flutter?

From the Guidelines

Atrial flutter is characterized by a regular atrial rate of 250-350 beats per minute, saw-tooth pattern of P waves on ECG, and fixed or variable atrioventricular block, as outlined in the 2015 ACC/AHA/HRS guideline for the management of adult patients with supraventricular tachycardia 1. The key criteria for identifying atrial flutter include:

• Regular atrial rate of 250-350 beats per minute
• Saw-tooth pattern of P waves on ECG, particularly visible in leads II, III, and aVF
• Fixed or variable atrioventricular (AV) block, often 2:1 or 4:1
• Absence of an isoelectric baseline between P waves These criteria are essential for diagnosing atrial flutter, as it can be mistaken for other arrhythmias, particularly atrial fibrillation 1. To diagnose atrial flutter, clinicians should perform a 12-lead ECG and look for these characteristic features, as recommended in the 2015 ACC/AHA/HRS guideline 1. Additional diagnostic tools may include 24-hour Holter monitoring or event recorders for intermittent symptoms. Understanding these criteria is crucial because atrial flutter can have significant implications for patient management, including the need for rate control medications, anticoagulation to prevent thromboembolism, and consideration of rhythm control strategies such as cardioversion or catheter ablation 1.

From the Research

Diagnostic Criteria for Atrial Flutter

The diagnostic criteria for atrial flutter can be identified through various electrocardiogram (ECG) characteristics, including:

• Presence of F waves in the frontal plane leads 2
• F waves in V(1) 2
• Sawtooth F waves 3, 4, 5
• Rate and regularity of ventricular response 2
• Frontal plane F waves and regular or partially regular ventricular response 2

ECG Characteristics

The ECG characteristics of atrial flutter can vary depending on the type of flutter, including:

• Typical right atrial flutter: sawtooth-like flutter waves starting negative in II, III, and aVF, with a steep slope upwards to the isoelectric line 4
• Right atrial flutter in a clockwise rotation: positive or biphasic flutter waves 4
• Left atrial flutter: heterogeneous flutter waves, typically positive in V1 4
• Typical atrial flutter: classic "sawtooth" pattern of flutter waves with negative polarity in leads II, III, and aVF 5

Classification and Nomenclature

The classification and nomenclature of atrial flutter have evolved over time, with various terms being used to describe the condition, including:

• Common, uncommon, typical, reverse typical, or atypical flutter 3
• CTI-dependent macro-re-entrant atrial tachycardia 6
• Cavotricuspid isthmus (CTI)-dependent re-entry 6