Discussion
We found a significant difference in the activation patterns between sinus rhythm and HB pacing. During sinus rhythm the earliest site of myocardial activation was in the LV septum and during HB pacing it was in the RV. The activation pattern of the LV was different in sinus rhythm (apex to base) when compared to HB (high septum to apex). Para-Hisian or non-selective HB pacing leads to simultaneous activation of the HB and adjacent myocardium.(3) This study suggests that during HB pacing, local myocardial capture can be present despite a narrow QRS and an isoelectric interval on surface ECG between pacing and earliest V.
1. Yancy CW, Jessup M, Bozkurt B et al. 2017 ACC/AHA/HFSA Focused Update of the 2013 ACCF/AHA Guideline for the Management of Heart Failure: A Report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines and the Heart Failure Society of America. J Am Coll Cardiol 2017;70:776-803.
2. Sharma PS, Dandamudi G, Herweg B et al. Permanent His-bundle pacing as an alternative to biventricular pacing for cardiac resynchronization therapy: A multicenter experience. Heart Rhythm 2018;15:413-420.
3. Cantu F, De Filippo P, Cardano P, De Luca A, Gavazzi A. Validation of criteria for selective his bundle and para-hisian permanent pacing. Pacing Clin Electrophysiol 2006;29:1326-33.