Show Summary Details
Page of

A single VPB during SVT/1 

A single VPB during SVT/1
Chapter:
A single VPB during SVT/1
Author(s):

Hein Heidbuchel

, Mattias Duytschaever

, and Haran Burri

DOI:
10.1093/med/9780198766377.003.0012
Page of

PRINTED FROM OXFORD MEDICINE ONLINE (www.oxfordmedicine.com). © Oxford University Press, 2021. All Rights Reserved. Under the terms of the licence agreement, an individual user may print out a PDF of a single chapter of a title in Oxford Medicine Online for personal use (for details see Privacy Policy and Legal Notice).

Subscriber: null; date: 05 August 2021

Introduction to the case

A 32-year-old man is presented with recurrent palpitations and documented narrow QRS tachycardia. During an electrophysiological study, after induction of the tachycardia, the introduction of a PVC during His refractoriness was performed, and the result was consequently reproducible (Figure 12.1).

Figure 12.1 PVC during His refractoriness. CS 9, 10: proximal coronary sinus; CS 5, 6: middle coronary sinus; CS 1, 2: distal coronary sinus; H: His electrogram; His d, distal; His p, proximal bipoles of a catheter in the His region; RVA, right ventricular apex; S, stimulation artefact

Figure 12.1
PVC during His refractoriness. CS 9, 10: proximal coronary sinus; CS 5, 6: middle coronary sinus; CS 1, 2: distal coronary sinus; H: His electrogram; His d, distal; His p, proximal bipoles of a catheter in the His region; RVA, right ventricular apex; S, stimulation artefact

Question

What is most likely mechanism of the tachycardia?

  1. A Typical AVNRT

  2. B Atypical AVNRT

  3. C AVRT using an accessory pathway

  4. D Atrial tachycardia

  5. E There are not enough data

Answer

C AVRT using an accessory pathway

Explanation

A single ventricular extrastimulus during supraventricular tachycardia/1

The tachycardia is a narrow complex supraventricular tachycardia. The fact that the PVC during His refractoriness terminates the tachycardia without conduction to the atrium indicates that an accessory pathway is present and is participating in the re-entry circuit. This cannot be the case in AT or AVNRT, not even over a bystander pathway.1,2

References

1. Veenhuyzen GD, Quinn FR, Wilton SB, Clegg R, Mitchell LB. Diagnostic pacing maneuvers for supraventricular tachycardias: part 2. Pacing Clin Electrophysiol 2012; 35: 757–69.Find this resource:

2. Huang SKS, Wood MA (2011). Catheter Ablation of Cardiac Arrhythmias, 2nd edn. Philadelphia: Elsevier Saunders.Find this resource: