Work

Modeling Transcatheter Mitral Valve Replacement with Anterior Leaflet Laceration using In Vitro and Computational Paradigms

Year: 2020

Type: article

Abstract: Objective: Transcatheter anterior leaflet laceration is thought to mitigate the risk of left ventricular outflow tract (LVOT) obstruction and valve thrombosis (due to flow stasis) following transcatheter mitral valve replacement (TMVR). However, few models have been proposed to simulate TMVR with anterior leaflet laceration. The current study utilizes two different models to examine the effectiveness of anterior leaflet laceration for decreasing flow stasis within the transcatheter valve and (2) mitigating LVOT obstruction. Methods: Flow stasis was studied in vitro using a validated left heart simulator with 2-D high-speed particle image velocimetry. A model 29 mm SAPIEN 3 valve positioned within the mitral annulus and a 3-D printed anterior leaflet were used to replicate TMVR with and without anterior leaflet laceration. Washout time and average washout velocity were quantified for each scenario. LVOT obstruction was studied computationally using a validated left heart model which utilizes patient-specific data from computed tomography. This computational model was used to simulate TMVR with and without anterior leaflet laceration to determine the change in simulated LVOT gradient and peak LVOT velocity for a single patient. Results: In the in vitro model, anterior leaflet laceration decreased washout time (0.33 seconds vs. 0.06 seconds) and increased the average washout velocity (0.043 m/sec vs. 0.056 m/sec) within the immediate vicinity of the transcatheter valve leaflets. In the patient-specific computational model, virtual anterior leaflet laceration was shown to decrease the LVOT gradient (17 mmHg vs. 7 mmHg) and decrease the peak LVOT velocity (2.96 m/sec vs. 1.93 m/sec) following virtual TMVR. Conclusions: The in vitro and computational models demonstrated that anterior leaflet laceration effectively decreases flow stasis within the valve and decreases LVOT gradient, respectively. These models have the potential to advance TMVR device design and offer important clinical insights regarding optimal implantation technique for mitigation of post-TMVR complications. KEYWORD: HVS-O-21 The authors do not declare any conflict of interest.

Source: Structural Heart

DOI: 10.1080/24748706.2020.1712971