Heart Failure -> Cardiac Resynchronization Therapy: -> Indications D-MP02 - Newer technologies in managing and predicting outcomes in HF and AF patients (ID 50) Moderated ePoster

D-MP02-04 - Electrocardiographic Predictors Of Complete Conduction Block In Patients With Left Bundle Branch Block (LBBB): Implications For Corrective Conduction System Pacing (ID 4)

 P. Razminia: Nothing relevant to disclose.


Background: Recent investigation of patients with LBBB pattern has shown that some patients do not demonstrate complete conduction system (CCB) and are unlikely to benefit from corrective conduction system pacing.
Objective: We sought to assess surface ECG predictors of complete conduction block (CCB) and response to His bundle pacing (HBP) in patients with LBBB.
Methods: Patients who underwent detailed intracardiac left septal mapping and HBP were analyzed. ECGs were reanalyzed utilizing CardioLab EP (GE Healthcare, Milwaukee, WI) and three conventional definitions of LBBB were applied: the ACCF/AHA/HRS definition (2009), Strauss criteria, and European Society of Cardiology criteria (2013). Additionally, novel criteria were assessed (time-to-notch ≥ 60ms in I, aVL, V5, or V6 plus absence of S-wave in V6 or R>S in V6).
Results: Seventy-five patients were studied: age 60 ± 14 years, 29% female, 48 (64%) patients demonstrated CCB, and 41 (54%) exhibited QRS correction with HBP. Average QRS was 164 ± 23 ms. The performance of ACCF/AHA/HRS, Strauss, ESC, and novel criteria are summarized in Table. The Strauss criteria demonstrated the greatest ability to include patients with CCB (OR 11.50, p= 0.003). Presence of time-to-notch ≥ 60 ms in I, aVL, V5, or V6 meaningfully predicted the favorable response to HBP more than other known criteria (OR 9.33, p= 0.002).
Conclusion: To our knowledge, this is the first investigation on the performance of commonly used LBBB definitions based on left septal activation mapping. The Strauss criteria reasonably identified CCB and assessment of time-to-mid QRS notching may better identify response to corrective HBP.