Coronary Perfusion Following a Transcatheter Aortic Valve Replacement in Either Reanimated Swine or Preserved Human Hearts.

BACKGROUND

Transcatheter aortic valve replacements (TAVRs) have become the predominant solution for treating patients with severe aortic valve stenosis. Meanwhile, procedural coronary obstructions and/or occlusions post-TAVR have subsequently become greater concerns as the use of TAVR increases in younger populations. Therefore, this preclinical study aimed to develop methodologies to assess coronary perfusion following a TAVR in both reanimated swine hearts and preserved human specimens perfused in a pulsatile system.

METHODS

This study employed Visible Heart® methodologies to functionally reanimate seven swine hearts. Endoscopic video cameras were used to enable direct visualization of the aortic root throughout these experimental procedures. Pressure wires were placed in the desired coronary arteries, and measurements were collected both before and after the TAVR. Subsequently, these reanimated hearts were scanned using micro-computed tomography (micro-CT), and the valve placements were assessed at resolutions >20 microns. Similar methodologies were utilized to study 13 perfusion-fixed human hearts, using a pulsatile pump, their valves were made functional, and the coronaries were perfused.

RESULTS

Pressure measurements from the left anterior descending arteries (LADs) were normalized to the recorded aortic pressures and the percentage difference from the pre- and post-TAVR and were correlated to the following features: commissural alignments (p = 0.274), valve implant depths (p = 0.546), left coronary sinus height (p = 0.127), left coronary ostium heights (p = 0.012), and estimated leaflet to ostium distance (ELOD) (p = 0.001).

CONCLUSIONS

These studies suggest that there may be stronger correlations between the ELOD and coronary perfusion post-TAVR than pre-procedural measurements of left coronary ostium heights. Left sinus heights, commissural alignments, and implant depths did not correlate significantly relative to coronary perfusions post-TAVR. These results could be further explored in various clinical studies and potentially used to provide additional insights into TAVR procedures across different patient anatomies, informing innovations in device design.