‍Introduction

His bundle pacing has recently emerged as a technique to avoid the negative effects of long-term right ventricular pacing.

Figure 1 Conceptual basis for differences in device EGM morphologies during selective–His bundle pacing (S-HBP) and nonselective (NS)-HBP.

                        DOI: 10.1161/CIRCEP.118.006878

Indications for HiS pacing:

• narrow QRS
• left bundle branch block (LBBB)
• long PR interval and narrow QRS

Figure 2 His bundle pacing across three classes of indications: 1) Narrow QRS, 2) LBBB and 3) Narrow QRS and long PR interval

https://doi.org/10.15420/aer.2018.6.2

Right ventricular apical pacing (RVP) and biventricular pacing (BVP) do not completely restore narrow QRS. His bundle pacing fully maintains or restores narrow QRS and ventricular synchrony with atrioventricular delay optimisation.

ECG features

The 12-lead ECG is considered the gold standard to differentiate between selective (S), nonselective (NS) His bundle pacing (HBP), and right ventricular septal capture in routine clinical practice.

1) Nonselective HBP

• a relatively narrow paced QRS morphology with the presence of a pseudo-delta wave and lack of an isoelectric baseline following the spike
• on device EGM assessment, a sharp immediate initial negative component was observed without an isoelectric segment as shown in red with an NFTime to Peak of 20 ms from the spike. The FFQRSd was 126 ms, as shown in blue.
  
  

Figure 3: Case example of nonselective–His bundle pacing (NS-HBP) and observed device EGM morphologies.

                      DOI: 10.1161/CIRCEP.118.006878

2) Selective HBP

• a narrow paced QRS morphology with an isoelectric baseline following the spike 
• on device EGM assessment, a discrete isoelectric segment followed by a positive NF EGM is observed as shown in red with an NF Time to Peak of 50 ms from the spike. The FFQRSd was 86 ms, as shown in blue.

Figure 4 Case example of selective–His bundle pacing (S-HBP) and observed device EGM morphologies. 

                     DOI: 10.1161/CIRCEP.118.006878

References

1) Saini A, Serafini NJ, Campbell S, Waugh WB, Zimberg R, Sheldon TJ, Kron J, Kalahasty G, Padala SK, Trohman R, Shepard RK, Koneru JN, Vijayaraman P, Ellenbogen KA, Sharma PS. Novel Method for Assessment of His Bundle Pacing Morphology Using Near Field and Far Field Device Electrograms. Circ Arrhythm Electrophysiol. 2019 Feb;12(2):e006878. doi: 10.1161/CIRCEP.118.006878. PMID: 30707036.

2) Vijayaraman P, Chung MK, Dandamudi G, Upadhyay GA, Krishnan K, Crossley G, Bova Campbell K, Lee BK, Refaat MM, Saksena S, Fisher JD, Lakkireddy D; ACC’s Electrophysiology Council. His Bundle Pacing. J Am Coll Cardiol. 2018 Aug 21;72(8):927-947. doi: 10.1016/j.jacc.2018.06.017. PMID: 30115232.

3) Payne J, Garlitski AC, Weinstock J, Homoud M, Madias C, Estes NAM. His bundle pacing. J Interv Card Electrophysiol. 2018 Aug;52(3):323-334. doi: 10.1007/s10840-018-0412-5. Epub 2018 Aug 13. PMID: 30105429.

4) Deshmukh P. His Bundle Pacing: Concept to Reality. Card Electrophysiol Clin. 2018 Sep;10(3):453-459. doi: 10.1016/j.ccep.2018.05.007. Epub 2018 Jul 21. PMID: 30172282.

5) Ravi V, El Baba M, Sharma PS. His bundle pacing: Tips and tricks. Pacing Clin Electrophysiol. 2021 Jan;44(1):26-34. doi: 10.1111/pace.14108. Epub 2020 Nov 26. PMID: 33174216.

6) Ali N, Keene D, Arnold A, Shun-Shin M, Whinnett ZI, Afzal Sohaib SM. His Bundle Pacing: A New Frontier in the Treatment of Heart Failure. Arrhythm Electrophysiol Rev. 2018 Jun;7(2):103-110. doi: 10.15420/aer.2018.6.2. PMID: 29967682; PMCID: PMC6020230.

7) https://www.uptodate.com/contents/ecg-tutorial-pacemakers