Which EKG finding is characteristic of atrial flutter?

Which EKG finding is characteristic of atrial flutter?

• A. Irregularly irregular rhythm
• B. Slow heart rate with AV block
• C. Sawtooth pattern on ECG
• D. Wide QRS tachycardia

Answer: (C)

Rapid, organized atrial activity in atrial flutter creates a distinctive sawtooth pattern of flutter waves on the ECG, reflecting atrial depolarizations at about 250–350 per minute. The ventricles usually respond through the AV node, so the ventricular rate is slower—commonly around 150 bpm with typical 2:1 conduction, though other conduction ratios can occur. This sawtooth appearance is best seen in leads II, III, aVF, and sometimes V1. The rhythm is often regular when AV conduction is constant, and the ventricular response can be slower or variable if AV block develops. Other patterns fit different conditions: irregularly irregular rhythms suggest atrial fibrillation; a slow heart rate with AV block isn’t the characteristic flutter pattern; wide QRS tachycardia points to ventricular tachycardia or SVT with aberrancy, not atrial flutter.

Rapid, organized atrial activity in atrial flutter creates a distinctive sawtooth pattern of flutter waves on the ECG, reflecting atrial depolarizations at about 250–350 per minute. The ventricles usually respond through the AV node, so the ventricular rate is slower—commonly around 150 bpm with typical 2:1 conduction, though other conduction ratios can occur. This sawtooth appearance is best seen in leads II, III, aVF, and sometimes V1. The rhythm is often regular when AV conduction is constant, and the ventricular response can be slower or variable if AV block develops. Other patterns fit different conditions: irregularly irregular rhythms suggest atrial fibrillation; a slow heart rate with AV block isn’t the characteristic flutter pattern; wide QRS tachycardia points to ventricular tachycardia or SVT with aberrancy, not atrial flutter.