Strain-based evaluation of septal function after left bundle branch area pacing

Area of Science:

• Cardiology
• Electrophysiology
• Cardiac Pacing

Background:

• Left Bundle Branch Area Pacing (LBBAP) involves deep septal lead implantation.
• The effect of this deep lead placement on septal contractility is not fully understood.

Purpose of the Study:

• To assess the impact of deep septal lead deployment in LBBAP on septal contraction and activation sequence.
• To evaluate changes in septal strain and identify contraction patterns during pacing.

Main Methods:

• Prospective analysis of 84 adult patients undergoing LBBAP.
• Strain imaging (GLS, PSS) pre- and post-implantation, during intrinsic rhythm and VVI pacing.
• Assessment of septal strain curves and identification of contraction patterns.

Main Results:

• No significant change in intrinsic Peak Septal Strain (PSS) in patients with normal baseline function.
• Significant improvement in PSS for patients with reduced baseline septal function post-LBBAP.
• Four septal contraction patterns identified during VVI pacing; higher scores correlated with discoordinated activation and reduced ventricular function.
• Absence of a terminal R' wave in lead V1 predicted discoordinated septal contraction.

Conclusions:

• Deep septal lead placement for LBBAP typically does not impair mid-term septal contractility.
• Most patients maintain normal septal contraction patterns (I & II) after LBBAP.
• Absence of R' wave in lead V1 is associated with abnormal septal contraction and may impact LBBAP outcomes.