NORCET -4 , 2023: Identify the following ECG finding which is denoting in photograph?

NORCET -4 , 2023

Medical & Surgical Nursing

Easy

Appeared in: NORCET -4 , 2023

Explanation

The ECG demonstrates classic 'sawtooth' flutter waves between the QRS complexes, which is the pathognomonic sign of Atrial Flutter.
This rhythm originates from a large re-entrant circuit within the atria, leading to rapid but organized atrial depolarization at a rate of 250-350 bpm.
The ventricular response is typically regular because the AV node conducts these impulses at a fixed ratio (e.g., 2:1, 3:1, or 4:1), as seen in the image.
The QRS complexes are narrow, confirming that the origin of the rhythm is supraventricular (above the ventricles).

Option A: Atrial fibrillation is characterized by an 'irregularly irregular' rhythm and a chaotic baseline with no discernible P waves (fibrillatory waves), which is different from the regular rhythm and organized sawtooth waves seen in the image.
Option B: Ventricular tachycardia originates in the ventricles, resulting in wide QRS complexes (greater than 0.12 seconds). The ECG in the image shows narrow QRS complexes, ruling out a ventricular origin.
Option D: SVT (Supraventricular Tachycardia) is a broad term. While atrial flutter is a type of SVT, this option usually refers to other forms like AVNRT, which present as a rapid, regular rhythm but lack the distinct sawtooth pattern. 'Atrial flutter' is the most specific and accurate diagnosis.

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain ECG interpretation of supraventricular tachyarrhythmias as background academic context rather than a clinical decision trigger.
Like atrial fibrillation, atrial flutter significantly increases the risk of thromboembolism and stroke due to blood stasis in the non-contracting atria. Patients often require anticoagulation based on their CHA2DS2-VASc score.
The primary goals of management are to control the ventricular rate (rate control), restore sinus rhythm (rhythm control), and prevent stroke.
Achieving rate control in atrial flutter can sometimes be more difficult than in atrial fibrillation because of the organized nature of the atrial impulses.

How to Approach the Question

First, analyze the rhythm by looking at the R-R intervals. In this ECG, they are regular.
Next, examine the baseline for atrial activity. Instead of normal P waves, identify the characteristic 'sawtooth' pattern.
Measure the QRS duration. Note that the QRS complexes are narrow, which points to a supraventricular origin.
Based on the combination of a regular rhythm, narrow QRS, and sawtooth flutter waves, conclude the diagnosis is Atrial Flutter.
Systematically rule out the other options: Atrial Fibrillation (irregularly irregular), Ventricular Tachycardia (wide QRS), and generic SVT (lacks sawtooth pattern).

Concept Tested & Keywords

Concept Tested: ECG interpretation of supraventricular tachyarrhythmias.
Stem keywords: ECG finding, photograph, arrhythmia
Lead-in keywords: Identify
Clinical cues: The presence of a sawtooth pattern on the ECG is a key diagnostic clue.

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