Left Bundle Branch Area Pacing guided by Continuous Uninterrupted Monitoring of the unipolar Pacing Characteristics.

Abstract

Introduction. During left bundle branch area pacing (LBBAP) lead implantation, intermittent monitoring of unipolar pacing characteristics validates LBB capture and can detect septal perforation. We aimed to demonstrate that continuous uninterrupted unipolar pacing from an inserted lead stylet (LS) is feasible and facilitates LBBAP implantation. Methods. Thirty patients (mean age 76 ± 14 years) were implanted with stylet-driven pacing lead (Biotronik Solia S60). In 10 patients (validation-group) conventional, interrupted implantation was performed, with comparison of unipolar pacing characteristics between LS and connector-pin (CP)-pacing after each rotation step. In 20 patients (feasibility-group) performance and safety of uninterrupted implantation during continuous pacing from the LS were analyzed. Results. In the validation-group, LS and CP-pacing impedances were highly correlated (R=0.95, p<0.0001, bias 12±37Ω). Pacing characteristics from LS and CP showed comparable sensed electrograms and paced QRS morphologies. In the feasibility-group, continuous LS-pacing allowed beat-to-beat monitoring of impedance and QRS morphology to guide implantation. This resulted in successful LBBAP in all patients, after a mean of 1±0 attempts, with mean threshold 0.81 ± 0.4V, median sensing 6.5mV [IQR 4.4-9.5] and mean impedance 624 ± 101Ω, and positive LBBAP-criteria with median paced QRS duration 120ms [IQR 112-152ms] and median pLVAT 73ms [IQR 68-80.5ms]. No septal perforation occurred. Conclusion. Unipolar pacing from the LS allows accurate determination of pacing impedance and generates similar paced QRS morphologies and equal sensed electrograms, compared to CP pacing. Continuous LS pacing allows real-time monitoring of impedance and paced QRS morphology, which facilitates a safe and successful LBBAP lead implantation.

Initial experience of left bundle branch area pacing using stylet‐driven pacing leads: A multicenter study

“…Screwing of the SDL towards a deep septal position was further guided by contrast injections, unipolar paced QRS morphology and monitoring of unipolar pacing impedance to achieve LBBAP. While deploying the lead in the septum, unipolar pacing was applied either intermittent at different steps during lead progression while other operators preferred continuous unipolar pacing while screwing the lead in the septum 14 . Unipolar pacing impedances were measured either on the lead pin or the stylet to allow for continuous pacing while screwing (Figure 1).…”

“…Unipolar pacing impedances were measured either on the lead pin or the stylet to allow for continuous pacing while screwing (Figure 1). 14 …”

“…While deploying the lead in the septum, unipolar pacing was applied either intermittent at different steps during lead progression while other operators preferred continuous unipolar pacing while screwing the lead in the septum. 14 Unipolar pacing impedances were measured either on the lead pin or the stylet to allow for continuous pacing while screwing (Figure 1). 14 Upon each new screw attempt, the lead was removed out of the delivery sheath and inspected for any remaining tissue at the helix.…”

“…14 Unipolar pacing impedances were measured either on the lead pin or the stylet to allow for continuous pacing while screwing (Figure 1). 14 Upon each new screw attempt, the lead was removed out of the delivery sheath and inspected for any remaining tissue at the helix. In case any remaining tissue at the helix was observed, the helix was cleaned before a new screw attempt was started.…”

“…19 This so-called entanglement effect occurs when the Fourthly, impedance monitoring is easily achieved by connecting the pacing clamp to the stylet, allowing for continuous pacing and impedance monitoring when screwing. 14 Finally, the delivery sheaths, used to target SDL towards deep septal positions, have a larger diameter and are more supportive compared to the delivery sheaths currently used with LLL.…”