A 78 year old lady sought medical attention for palpitations with documented regular wide complex tachycardia with a left bundle branch block (figure [1](#fig-cap-0001)) as well as atrial fibrillation. She presented for a catheter ablation for atrial fibrillation and presumed CTI-dependent atrial flutter. As a part of the procedure, we performed an electrophysiology study. We performed pacing manoeuvres to evaluate for the presence of a concealed accessory pathway. She had an underlying left bundle branch block observed in sinus rhythm. Results of para-Hisian pacing maneuver are displayed in figure [2](#fig-cap-0002) with intracardiac electrograms and corresponding 12-lead ECG. Para-Hisian pacing is performed at a constant pacing interval through the distal electrode of the His bundle catheter. There is a decapolar catheter in the coronary sinus with the proximal electrode positioned at the Os. Here are some questions to consider: There are 4 different paced morphologies observed. What does each one of these represent? How can we interpret the findings of this maneuver? What role does pre-existing left bundle branch block play in our interpretation?