Which pacing location has been associated with longer implant times and higher thresholds?

The association of longer implant times and higher thresholds with pacing at the low/mid RV septum can be attributed to anatomical and physiological factors specific to that area. When pacing is performed in this region, it often necessitates more intricate navigation and positioning of the lead compared to other locations. This can lead to extended time during the implantation process.

Additionally, the low/mid RV septum is characterized by a more challenging myocardial architecture, which can create variance in tissue properties. As a result of these factors, pacing leads in this region may be less efficient at capturing the myocardium, leading to higher capture thresholds. In contrast, other locations such as the RV apical pacing, RVOT pacing, and His bundle pacing may not experience these same challenges, often resulting in shorter implant times and lower threshold requirements.

Ultimately, the anatomical complexities and variances in capture efficiency in the low/mid RV septum contribute to the observed longer implant times and elevated thresholds associated with this pacing site.