SVT will be which of the following?

• A. Sinus tach 150+
• B. Atrial tach 150+
• C. Aflutter 150+
• D. Junctional tach 150+

Answer: (D)

Supraventricular tachycardia is a fast heart rhythm that starts above the ventricles. Among the common SVTs, a junctional tachycardia is a classic example because it originates in the AV junction. That origin produces a narrow QRS tachycardia with a rate typically around 150 beats per minute. The atrial activity can be tricky to see: P waves may be buried in or occur after the QRS complex, or they may be inverted if atrial activation is retrograde. This combination—rapid, narrow-complex rhythm with P waves that aren’t clearly preceding the QRS—fits junctional tachycardia well.

In contrast, sinus tachycardia comes from the SA node and usually shows normal, clearly visible P waves before each QRS, with a rate that rises with activity or stress and can approach similar numbers but keeps the P waves distinct. Atrial tachycardia is an ectopic focus in the atria, yielding a rapid rhythm with P waves that have an abnormal shape before each QRS. Atrial flutter shows a characteristic sawtooth pattern of flutter waves, typically at a higher atrial rate and with a different atrial-to-ventricular relationship.

So the rhythm described as a fast SVT arising from the AV junction is a junctional tachycardia.