Association Between Inferior Vena Cava Location and the Number of Deployments of a Leadless Pacemaker

While some patients faced the difficulty to implant leadless pacemaker, the relationship between inferior vena cava (IVC) location and procedural difficulty was uncertain.

We conducted a single-center, cross-sectional study including 96 consecutive patients who underwent implantation of Micra leadless pacemakers between July 2022 and November 2024. Based on the positional relationship between the IVC and the right ventricular septum assessed by preprocedural computed tomography, patients were classified into right-sided and left-sided IVC groups. The primary outcome was multiple deployments defined as the number of device deployments ≥ 2.

A total of 96 patients were analyzed, including 81 in the right-sided and 15 in the left-sided IVC group. The mean age was 84, and 55 (57%) were male patients. Multiple deployments were observed in 39 (41%) patients. The risk of the primary outcome was significantly higher in the left-sided IVC group than in the right-sided (67% vs. 36%), with an adjusted odds ratio of 9.5 (95% CI: 1.5-58.7, p = 0.02). Procedure time was numerically longer in the left-sided group (36 vs. 25 min, p = 0.11). Pericardial effusion occurred only in two patients in the right-sided group, none requiring intervention.

The left-sided IVC was associated with multiple deployments of a leadless pacemaker and preoperative computed tomography was useful in assessing the procedural difficulty.