Advertisement

To the Editor— Left bundle branch area pacing in coronary venous lead failure or nonresponse to biventricular pacing: Can cardiac resynchronization therapy be healing?

Published:September 24, 2022DOI:https://doi.org/10.1016/j.hrthm.2022.08.040
      We congratulate Vijayaraman et al
      • Vijayaraman P.
      • Herweg B.
      • Verma A.
      • et al.
      Rescue left bundle branch area pacing in coronary venous lead failure or nonresponse to biventricular pacing: results from International LBBAP Collaborative Study Group.
      for their significant work recently published in Heart Rhythm Journal. The authors draw a conclusion that left bundle branch area pacing (LBBAP) is a viable alternative to cardiac resynchronization therapy (CRT) in patients who failed conventional biventricular pacing (BVP) owing to coronary venous lead failure or who were nonresponders. However, detailed information on the clinical outcomes in patients with left bundle branch block (LBBB), right bundle branch block (RBBB), or intraventricular conduction delay (IVCD) was not specifically reported. Recently, Chen et al
      • Chen X.
      • Ye Y.
      • Wang Z.
      • et al.
      Cardiac resynchronization therapy via left bundle branch pacing vs. optimized biventricular pacing with adaptive algorithm in heart failure with left bundle branch block: a prospective, multi-centre, observational study.
      has indicated that LBBAP demonstrated better electromechanical resynchronization and higher super-response than did BVP in heart failure with left ventricular (LV) ejection fraction ≤ 35% and typical LBBB. Apparently, LBBAP is superior to BVP in patients with heart failure and typical LBBB. During LBBAP, electromechanical contraction of the LV is earlier than that of the right ventricle. Therefore, LBBAP may not correct heart failure with RBBB. In patients with typical LBBB, it was conceivable that LBBAP provided clinical benefits due to LBBB was corrected by bypassing the block site and therefore a full recovery of LV synchronization. In the study by Li et al,
      • Li Y.
      • Yan L.
      • Dai Y.
      • et al.
      Feasibility and efficacy of left bundle branch area pacing in patients indicated for cardiac resynchronization therapy.
      only moderate improvement in LV function was observed in patients with IVCD when treated with LBBAP alone. Therefore, LBBAP may not significantly improve heart failure with other etiologies beyond typical LBBB. In the present study, LBBAP-optimized CRT (LOT-CRT) was performed in 6.5% of nonresponders, which is theoretically more effective for patients with atypical LBBB or IVCD than LBBAP. Therefore, we wonder whether LBBAP or LOT-CRT improves the clinical outcomes in patients with RBBB, atypical LBBB, or IVCD. It would be interesting to reanalyze the data to address this issue. The lack of detailed information on the patient outcomes in different etiologies in this study makes it confusing to understand whether LBBAP or LOT-CRT is beneficial in all patients with coronary venous lead failure or nonresponse to BVP.
      To read this article in full you will need to make a payment

      Purchase one-time access:

      Academic & Personal: 24 hour online accessCorporate R&D Professionals: 24 hour online access
      One-time access price info
      • For academic or personal research use, select 'Academic and Personal'
      • For corporate R&D use, select 'Corporate R&D Professionals'

      Subscribe:

      Subscribe to Heart Rhythm
      Already a print subscriber? Claim online access
      Already an online subscriber? Sign in
      Institutional Access: Sign in to ScienceDirect

      References

        • Vijayaraman P.
        • Herweg B.
        • Verma A.
        • et al.
        Rescue left bundle branch area pacing in coronary venous lead failure or nonresponse to biventricular pacing: results from International LBBAP Collaborative Study Group.
        Heart Rhythm. 2022; 19: 1272-1280
        • Chen X.
        • Ye Y.
        • Wang Z.
        • et al.
        Cardiac resynchronization therapy via left bundle branch pacing vs. optimized biventricular pacing with adaptive algorithm in heart failure with left bundle branch block: a prospective, multi-centre, observational study.
        Europace. 2022; 24: 807-816
        • Li Y.
        • Yan L.
        • Dai Y.
        • et al.
        Feasibility and efficacy of left bundle branch area pacing in patients indicated for cardiac resynchronization therapy.
        Europace. 2020; 22: ii54-ii60

      Linked Article