Utility of the Visible Heart® and Micro-CT Imaging to Optimize the Treatments of Bifurcation Stenting

Abstract

Using the Visible Heart® Apparatus and methodologies allows for the ability to reanimate large mammalian hearts, including human, and thus to perform bifurcation stenting in an in vitro setting. This allows for novel uses of multimodal imaging for assessing/testing previous, current and future clinical recommendations for bifurcation techniques, without risking a living patient. After performing such procedures, high resolution 3D models were obtained via micro-CT imaging, which then allows for post implant device/tissue interface analyses. Utilizing reanimated swine hearts, we were able to uniquely visualize how the various bifurcation techniques performed could be optimized in specific anatomies. These findings again confirm that the Visible Heart® Apparatus is a valuable platform that should be used to further understand how next generation stents and/or bifurcation techniques can best be utilized. Recently, our laboratory also had the privilege to perform bifurcation stenting within three reanimated human hearts using the same methodologies. Additionally, similar PCI procedures were performed in three perfusion-fixed human hearts as further means to compare the differences in stenting technique and to identify potential differences between procedures performed in fixed versus reanimated human hearts. Also, it was identified that after the formalin fixation process, desecrations of the coronary vessels could readily be induced in healthy human hearts, while those presenting with coronary artery disease elicited little to no effects due to the plaque formations. If this holds true, this will open the Visible Heart® Laboratories’ human heart library of over 580 specimens, to perform clinically relevant bifurcation stenting techniques. Finally, a novel research method of detecting stent malappositions was created, as the current standard for intracoronary imaging, optical coherence tomography (OCT), has its limitations when there are multiple stents implanted. This method was then used alongside OCT in a step-by -step bifurcation intervention performed in a formalin fixed human heart. It was shown that stent apposition continuously improves if the operator adheres to the latest published guidelines; however future investigations should be performed in more diseased human hearts from the Visible Heart’s human heart library to focus on other bifurcation techniques and the consequences of straying from these guidelines in each case.