Association Between Current of Injury Magnitude and Intraoperative R-Wave Amplitude Fluctuation After Pacing Lead...

Area of Science:

• Cardiology
• Biomedical Engineering
• Electrophysiology

Background:

• Pacing threshold adequacy and lead stability are crucial for successful pacemaker implantation.
• Current of injury (COI) magnitude predicts these parameters post-fixation.
• Intraoperative R-wave amplitude fluctuations can occur despite adequate COI.

Purpose of the Study:

• To determine if R-wave amplitude fluctuations correlate with COI magnitude.
• To assess if early electrogram (EGM) patterns can predict these fluctuations.
• To identify predictors for favorable R-wave amplitude increases.

Main Methods:

• Continuous EGM recording in 109 right ventricular septal pacing cases.
• Categorization of R-wave amplitude fluctuation patterns: Dipper, Riser, and Other.
• Primary outcome: favorable R-wave amplitude increase (final > initial value).

Main Results:

• Dipper-type patterns (60%) and Riser-type patterns (38%) were most common.
• Dipper-type showed initial R-wave amplitude < COI, shifting to > COI.
• Favorable increases in Dipper-type cases predicted within 6 minutes (sensitivity 0.82, specificity 0.61).
• Riser-type patterns consistently showed favorable amplitude increases.

Conclusions:

• Most successful lead implantations exhibit Dipper or Riser R-wave amplitude patterns.
• Early EGM patterns within 6 minutes post-fixation predict favorable R-wave amplitude increases.
• This prediction aids in assessing lead stability during pacemaker procedures.