His bundle pacing implantation in octogenarian patients: a substudy of the PACE-CONDUCT trial

Abstract

Abstract Background His bundle pacing (HBP) is gaining recognition as a valuable alternative for the management of various cardiac conduction disorders. This substudy, conducted within the framework of the PACE-CONDUCT trial, investigates the outcomes of HBP implantation in patients aged 80 years and older, comparing them with a younger cohort. Methods We examined a total of 61 consecutive patients who underwent HBP implantation, utilizing DDD pacemakers, CRT-P, or CRT-D devices, during the years 2021 to 2023. Patients were categorized into two subgroups: those aged younger than 80 years and those aged 80 years or older. The mean age of the entire cohort was 73 years, spanning from 51 to 86 years, with 15 patients (comprising 24.6% of the total) falling into the octogenarian category. His bundle threshold was assessed on the day of implantation, one day post-implantation, and four weeks post-implantation. All HBP implantations were deemed successful, incorporating both selective and non-selective His bundle pacing. Complications were classified as major (necessitating lead or pocket revision) or minor (requiring no revision). Threshold values were converted to volts per milliseconds (volts x milliseconds) for statistical analysis, conducted with IBM SPSS Statistics 29.0. Results Initial analysis revealed a consistent success rate of HBP implantation across all patients, with no discernible differences between the two age groups. Threshold measurements at the day of implantation and after one day indicated no differences between the younger and the older group. However, at the four-week mark, a statistically significant lower threshold of His bundle pacing was observed in the octogenarian group (one-sided p-value 0.028), suggesting a faster stabilization to the chronic threshold of the active fixation His Bundle lead. The comparison of major and minor complications between the age groups, conducted using chi-square tests, revealed no age-related discrepancies. Conclusions This substudy of the PACE-CONDUCT trial underscores the feasibility and safety of His bundle pacing implantation in octogenarian patients, comparable to their younger counterparts. While no initial threshold variations are observed, the octogenarian group demonstrated improved His bundle pacing thresholds approximately four weeks post-implantation. Importantly, the study revealed no heightened complication risk associated with advanced age, affirming that very old patients aged 80 or older can derive the benefits of His bundle pacing without increased complication rates. Given the relatively modest patient cohort in this study, further investigations are warranted to validate and extend these findings.T-tests and Chi square tests