Computational analysis of intracardiac collision risk and optimal site for right ventricular leadless left bundle branch area pacing: A simulation study

Figures

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  Figure 1. A: Cardiac computed tomography images were segmented and used to generate a (B) biventricular mesh, including the PMs, TV apparatus, and an estimation of the conduction system. C: American Heart Association regions were mapped onto the left ventricular epicardium and right ventricular (RV) septum. Cylinders representing the leadless pacemakers were virtually implanted across the RV septum surface. D: The >50% collision risk with the RV wall (orange), PM (green), and TV structures (blue). E: Left bundle branch area pacing regions were plotted. Non-RV septal regions are gray. L-PM = leadless pacemaker; PM = papillary muscles and moderator band; TV = tricuspid valve.

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  Figure 2. Leadless pacemakers (L-PMs) were virtually implanted across the right ventricular (RV) septal wall, and the deformations of the cardiac tissue were tracked. Collision with the RV intracardiac structures at any point throughout the 10 phases of the cardiac cycle was assessed for each implant location for each patient. 3 representative implant locations of the Micra TPS on a patient case are shown here. Top: (pink) L-PM collides with the tricuspid valve apparatus. Middle: (blue) L-PM does not collide with the intracardiac structures. Bottom: (yellow) L-PM collides with the RV free wall and the papillary muscles throughout the cardiac cycle.

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  Figure 3. Probability maps of the likelihood of collision of the Aveir AR leadless pacemaker with the intracardiac structures (RV endocardium, PMs, and TV structures pacing at sites across the RV septum). The Aveir AR plot shows the RV septal pacing regions where more than 50% of cases would have collision with the RV (orange), TV (blue), or PM intracardiac structures (green). Lines denoting 20 mm below the TV annulus (yellow dashed line) for all 10 cases are shown. PM = papillary muscles and moderator band; RV = right ventricular; TV = tricuspid valve.

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  Figure 4. Plots of the collision risks with leadless pacemaker designs at different lengths within the RV septal AHA regions. The collision risks with the RV wall (top row), tricuspid valve structures (second row), papillary muscles and moderator band structures (third row), and the combined collision risk (bottom row) are presented. AHA = American Heart Association; RV = right ventricular; SD = standard deviation.

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  Figure 5. The combined collision risk throughout the cardiac cycle for 10 patients at different lengths of leadless pacemakers based on the Aveir AR device volumes plotted on the right ventricular septal American Heart Association regions. The results for the initial dimensions of the Aveir AR are boxed in red. Implantation areas where the leadless pacemaker would collide with the tricuspid valve apparatus (blue), papillary muscles and moderator band (green), and the right ventricular wall (orange) in >50% of cases and yellow dashed lines representing 20 mm under the tricuspid valve annulus are shown.

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  Figure 6. Plots of the collision risks with leadless pacemaker designs (Micra TPS [left], Aveir AR [middle], and Aveir VR [right]) at different lengths within the LBBAP regions. LBBAP = left bundle branch area pacing; RV = right ventricular; SD = standard deviation.