Cardiovascular Implantable Electronic Devices -> Bradycardia Devices: -> Clinical Trials D-PO02 - Poster Session II (ID 47) Poster

D-PO02-088 - Anatomical Approach For Permanent His-bundle Pacing Using Coronary Sinus Ostium As A Reference (ID 1008)

 D. Yoshimoto: Nothing relevant to disclose.


Background: There is a definite learning curve for performing His-bundle pacing (HBP) because HBP requires an understanding of fundamental aspects of electrophysiology and cardiac anatomy. Usually, it is necessary to adjust and handle the sheath finely using intracardiac electrograms as a reference depending on the patients.
Objective: To investigate successful permanent HBP points retrospectively and verify anatomical approach for HBP using the retrospective data prospectively.
Methods: When we performed His-bundle mapping using the SelectSecure lead through the C315 HIS delivery sheath, we inserted a retractable active-fixation lead which was implanted for atrium later into coronary sinus (CS) by shaping stylet beforehand. Successful HBP points which were defined as HBP threshold<2V at 1ms were investigated retrospectively with a focus on the CS ostium visualized by the lead at CS in the 20 degree right anterior oblique. We fixed the CS ostium as the vertex of the angle and measured the angle between the successful HBP point and the horizontal axis as “theta (θ) of HBP”. Based on the retrospective study, we prospectively verified an anatomical approach for HBP without intracardiac electrograms.
Results: Between January 2018 and April 2019, 18 patients with AVB who achieved successful permanent HBP were enrolled. During a diastole, mean θ was 54.7±6.1; median θ was 53.5 (interquartile range: IQR 51.75-58), and during a systole, mean θ was 49.3±8.3; median θ was 50.5 (IQR 44.75-54). Mean ventricular amplitude at the implantation site was 5.1±2.2 mV. In prospective study, CS ostium was visualized by the retractable lead for atrium or delivery wire inserted into CS and 55-degree (diastolic θ) line was drawn on the screen, and we performed pace mapping on the line if a ventricular amplitude was about 3-7 mV using a Medtronic pacing system analyzer. Between May 2019 and September 2019, 14 patients underwent HBP by the anatomical approach. Thirteen patients (92.8%) achieved HBP on the 55-degree line during a diastole and the number of pace mappings was 1.7±1.4.
Conclusion: The anatomical distribution of successful HBP points with a focus on CS ostium tended to converge and might be useful to predict the success sites of permanent HBP.