We will now continue with the tachyarrhythmias; these may be due to either enhanced automaticity or reentry, or both. Premature complexes of atrial, junctional, and ventricular origin will be discussed first, and this provides a natural lead into the subsequent discussion of the tachycardias, since the mechanisms (enhanced automaticity and reentry) are the same.
The supraventricular tachycardias (SVT’s) will include the atrial tachycardias, atrial flutter, and atrial fibrillation. We will also include SVT’s that are due to reentry in the AV junction utilizing primarily the AV node (AV nodal reentry tachycardia or AVNRT) and, optionally, we will include those using the AV node plus an accessory pathway (AV reentry or reciprocating tachycardia, also termed AVRT). Next, we will discuss accelerated junctional rhythm.
The ventricular tachycardias will include accelerated ventricular rhythm, ventricular tachycardia (VT), torsade de pointes, and ventricular fibrillation.