Transcatheter Aortic Valve Deployment: Interactions Between Native Leaflets and Coronary Ostia

During the delivery of a transcatheter aortic valve, the native leaflets are pressed toward the vessel wall when the stented valve is deployed, but the proximity of the native leaflets to the coronary ostia following deployment is not fully understood. Fluoroscopic (F) and endoscopic (E) video footage was gathered from isolated human hearts $(n=3)$⁠. Balloon valvuloplasty (BAV) was performed with a non-compliant balloon, followed by contrast injection into the coronary ostia. Images (F) captured the perpendicular distance from the balloon to the ostia (ostium depth). A nitinol stent was delivered to the aortic position trans-apically. Images (E) measured the distance between the native aortic leaflet and the lowest point of the coronary ostium (ostium height). Additionally, cadaveric hearts $(n=23)$ underwent extensive anatomical analyses using a 3D digitizing arm in addition to the described procedures. BAV in perfusion fixed hearts gave left and right ostium depths of $5.28±1.49$ and $5.34±1.85$⁠. Images (E) from the perfusion fixed human hearts showed left and right ostium heights of $3.2±2.9$ mm and $4.3±2.4$⁠, respectively. 2 of the 23 perfusion fixed human hearts studied had negative ostia heights, but the effect on coronary flow is not known.