Which arrhythmia features abnormal P waves that appear in a sawtooth configuration?

The presence of abnormal P waves arranged in a sawtooth configuration is characteristic of atrial flutter. This specific pattern occurs due to the rapid reentrant circuits in the atria that produce a rapid succession of atrial depolarizations. The distinct "sawtooth" appearance, often referred to as "F-waves," is typically observed in the inferior leads of an electrocardiogram (ECG), such as II, III, and aVF, where the waves alternate distinctly.

In atrial flutter, the atrial rate can be quite fast, typically around 250 to 350 beats per minute, leading to the unique sawtooth pattern. This arrhythmia results from a more organized electrical activity compared to chaotic rhythms associated with conditions like ventricular fibrillation, which lacks distinct P waves and has a completely erratic waveform. Similarly, atrial tachycardia and junctional rhythm demonstrate different patterns in P wave morphology and frequency, which do not match the sawtooth configuration characteristic of atrial flutter. Understanding these features helps in identifying atrial flutter accurately in clinical practice.