Abstract 13622: Current of Injury is an Indicator of Lead Depth and Acute Perforation During Left Bundle Branch Pacing Lead Implantation

Abstract

Background: Left bundle branch(LBB)pacing has emerged as a favorable option that utilizes cardiac conduction system. Monitoring lead depth in the septum is crucial to reach the LBB area and to avoid lead perforation but lacks informative approach. We aimed to assess the hypothesis that current of injury (COI) is a useful tool in guiding depth of lead and forecasting perforation. Methods: Consecutive patients who received LBB pacing with distinct LBB potential were enrolled from January 2018 to December 2020. Unipolar intracardiac electrogram was recorded from both tip and ring electrode at the time of lead fixation. The maximum amplitude of ST-segment elevation from baseline was defined as COI. Results: LBB pacing lead implantation was attempted for 1223 times in 512 patients (age 66.25 ± 15.20 years, 310 male). Discrete COI (ST-segment elevation more than 25% of intrinsic R wave amplitude) was present in 92.70% of the cases (1134/1223) on tip electrode while only in 68.1% of the cases (833/1223) on ring electrode. COI tip/COI ring was correlated with the lead depth determined by sheath angiography (Spearman’s Correlation Coefficient=-0.624, p =0.000). Acute lead perforation has occurred in 11 cases when COI was either absent or very low on tip electrode. Among them, only eight cases, noted as microperforation, displayed significant COI on ring electrode, and COI tip/COI ring was extremely low (0.063, 0.035-0.123). The COI tip/COI ring<1 is associated to lead perforation (OR: 30.24, 6.47 -141.3, p=0.000). Sensitivity, specificity, and positive and negative predictive values of COI tip/ring<1 as an early marker for lead perforation were 81.8%, 87.1%, 54.2% and 99.8%, respectively. Conclusions: In conclusion, COI tip/ring could help to understand the depth of lead inside ventricular septum. Lack of COI on tip electrode or a very low COI tip/COI ring may signal lead perforation.