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This study assessed the long-term hemodynamic functional performance of the new Inspiris Resilia aortic valve after accelerated wear testing (AWT).

Transcatheter aortic valve replacement devices vary in leaflet material and in the height for which leaflets attach to the stented valve frame. Combinations of these features can influence leaflet dynamics, neo-sinus geometries, and fluid dynamics, thereby reducing or exacerbating the potential for blood flow stasis and leaflet thrombosis. To investigate these interconnected relationships, this study evaluated the effects of transcatheter valve leaflet type [porcine versus bovine pericardium] and the leaflet-stent attachment height (low, mid, and high) on flow stasis and potential for leaflet thrombosis. Transcatheter valve models were manufactured and tested within an aortic simulator under pulsatile left heart hemodynamic conditions. Transvalvular hemodynamics, leaflet kinematics, and flow structures were evaluated by direct measurement, high-speed imaging, and two differing techniques of particle image velocimetry. Transcatheter valves with porcine pericardial leaflets were observed to be less stiff, exhibit a lesser resistance to flow, were associated with reduced regions of neo-sinus flow stasis, and superior sinus washout times. More elevated attachments of the leaflets were associated with less neo-sinus flow stasis. These initial results and observations suggest combinations of leaflet type and stent attachment height may reduce transcatheter aortic valve flow stasis and the potential for leaflet thrombosis.

Introduction:The purpose of this study was to investigate the hemodynamic impact of LAMPOON (Laceration of the Anterior Mitral leaflet to Prevent Outflow ObstructioN) in transcatheter mitral valve replacement (TMVR) using patient-specific in silicomodeling.Methods:Eight subjects from the LAMPOON investigational device exemption trial were included. All subjects were at prohibitive risk of outflow tract obstruction from TMVR based on computed tomography (CT), and underwent successful LAMPOON immediately followed by TMVR. A validated computational fluid dynamics (CFD) model was used to compare simulated hemodynamics and 3D flow patterns between two modeled conditions: 1) TMVR with LAMPOON and 2) TMVR without LAMPOON. Using the post-procedure CT scans, anatomical models of TMVR with LAMPOON were created for each subject. The open transcatheter valve cells were then virtually closedto model TMVR without LAMPOON for each subject. Finally, CFD was performed for each condition to simulate the systolic flow fields.Results:As compared to TMVR without LAMPOON, TMVR with LAMPOON resulted in lower peak velocity, lower peak LVOT gradient, and higher peak LVOT effective orifice area by 13±6% (p=0.004), 28±14% (p=0.008), and 15±8% (p=0.002), respectively. LAMPOON provided flow communication through exposed cells of the transcatheter valve, thereby decreasing the flow constriction and reducing flow stasis in the vicinity of the neo-LVOT (Figure). The hemodynamic benefit of LAMPOON was observed to be greater in subjects with a smaller neo-LVOT area measured post-implant (p<0.001).Conclusions:In silicomodeling allowed for a quantitative patient-specific comparison of TMVR with and without LAMPOON, which is impossible to study clinically. The LAMPOON procedure improved simulated hemodynamics in all subjects, with a greater hemodynamic impact observed in subjects with a smaller post-implant neo-LVOT area.

Introduction:The off-label use of transcatheter aortic valves (TAV) in the mitral valve (MV) is a developing alternative for high-risk patients with mitral annulus calcification (MAC), degenerated bioprostheses, and failed annuloplasties. The risk of TAV thrombosis has been seen in the AV, and it is believed that the MV leaflets will have an impact on thrombosis in the MV. Recently, LAMPOON has been used to proactively treat left ventricular outflow tract obstruction by lacerating the anterior mitral leaflet (AML) before transcatheter MV replacement. This study investigates the effects of LAMPOON on the flow region between the TAV leaflet and AML (the neo-sinus).Methods:MV leaflets were 3-D printed from ?CT images of a porcine MV and fixtured inside the LV phantom of the left heart simulator. A previously validated in-house TAV model was deployed at an 80/20 ventricle/atrial ratio to simulate a 29 mm SAPIEN 3 valve-in-MAC. 2-D high-speed particle image velocimetry was performed to measure the time-resolved velocity field within the neo-sinus. Images were acquired along the central long-axis plane over 36 consecutive cycles. The experiments were performed at three cardiac outputs (2.5, 5.0, and 6.5 Lpm) at a rate of 70 bpm and 100 mmHg peak MV gradient. Two AML conditions were used: Intact and 100% LAMPOON.Results:At 2.5 (Figure 1), 5.0, and 6.5 Lpm, it was found that 100% LAMPOON had higher average velocities in the neo-sinus than Intact, and that all conditions showed maximum velocities over 0.1 m/s in the neo-sinus. This higher average velocity resulted from 100% LAMPOON having higher diastolic velocities in the neo-sinus compared to the stagnated diastolic flow with the Intact AML.Conclusions:In this in vitrostudy, the results showed that LAMPOON decreased stagnation in the neo-sinus during diastole and that all conditions had adequate neo-sinus flow during systole. This suggests that LAMPOON could lower the risk of thrombosis in the anterior MV neo-sinus.