HRCR December 2024 Quiz

Editorial note: The following quiz is related to the article Different levels of recruitment during conduction system pacing Johan van Koll and colleagues in the December 2024 issue of Heart Rhythm Case Reports.

1. In the case of conduction system pacing, decremental output pacing (threshold testing) may lead to various transitions in QRS morphology, reflecting different levels of conduction system capture. Which of the following transitions could be observed during decremental output pacing?

a
b
c
d

2. There are different electrical parameters which can be used to confirm capture of the left conduction system based on a 12-lead ECG. Transition in QRS morphology is the gold standard to assess capture. How is the transition from ns-LBBP to LVSP characterized?

a. Decrease in V6RWPT and decrease in terminal R or r amplitude in lead V1.
b. Increase in V6RWPT and decrease in terminal R or r amplitude in lead V1.
c. Increase in V6RWPT and increase in terminal R or r amplitude in lead V1.
d. Unchanged V6RWPT and unchanged terminal R or r amplitude in lead V1.

3. There are different electrical parameters which can be used to confirm capture of the left conduction system, based on 12-lead ECGs. Transition in QRS morphology is the gold standard to assess capture. How is the transition from ns-LBBP to s-LBBP characterized?

a. Prolongation of the QRS duration and unchanged V6RWPT.
b. Prolongation of the QRS duration and increased V6RWPT.
c. Shortening of the QRS duration and unchanged V6RWPT.
d. Shortening of the QRS duration and increased V6RWPT.

4. During decremental output pacing, a transition is observed. Which transition can be seen in this 12-lead ECG?

a. ns-LBBP -> s-LBBP
b. s-LBBP -> ns-LBBP
c. LVSP -> s-LBBP
d. Ns-LBBP -> LVSP