Predicting LVOT Obstruction After TMVR

Abstract

Keywords3D print; computer aided design; LVOT obstruction; transcatheter mitral valve replacement EVOLUTION OF CATHETER-BASED STRUCTURAL INTERVENTIONS HAS GIVEN PATIENTS LESS INVASIVE alternatives to surgery; however, the current generation of transcatheter heart valves (THV) are not specifically designed for mitral position implantation and have intrinsic geometry that may make mitral implantation suboptimal. Operators are faced with unique challenges with valve deliverability, embolism, and notably left ventricular outflow tract (LVOT) obstruction. Therefore, understanding the suitability of prosthesis delivery and implantation individualized to each heart is of paramount importance.Successful transcatheter mitral valve replacement (TMVR) depends on accurate sizing of the mitral annulus (Figure 1) and avoidance of LVOT obstruction. Incorporation of computeraided design and generation of 3-dimensional-printed heart models allows for ex vivo device bench testing in patient-specific anatomy (Figures 1 and 2). Modeling of proposed THV at different angles/depths of deployment into the LV allows estimation of LVOT obstruction of neo-LVOT/LVOT (Figure 3). We now aim to describe the utility of cardiac computed tomography ( Table 1) and ex vivo THV fit testing with 3-dimensional models to predict LVOT obstruction in TMVR.

Transcatheter Aortic and Mitral Valve‐in‐Valve Implantation Using the Edwards Sapien 3 Heart Valve

“…Preprocedural virtual valve implantation, performed using commercially available 3‐dimensional reconstruction software, and calculation of the neo‐LVOT area can assist preemptive identification of this complication (Figure 7). Preliminary studies suggest that a neo‐LVOT area of 250 mm 2 or larger is associated with a low risk of LVOT obstruction 36, 37…”

Use of Cardiac Computerized Tomography to Predict Neo–Left Ventricular Outflow Tract Obstruction Before Transcatheter Mitral Valve Replacement

“…For instance, improved software may improve consistency between readers in valve sizing and save time relative to standard CT postprocessing techniques. Some institutions have advocated using computer‐aided design solutions to simulate valve sizing and position as well as to assess the risk of potential LVOT obstruction . 3D printing techniques may also offer the potential for individual assessment of the device‐patient interaction, which may prove valuable in assessing potential complications, such as paravalvular regurgitation or neo‐LVOT obstruction .…”

Intentional Percutaneous Laceration of the Anterior Mitral Leaflet to Prevent Outflow Obstruction During Transcatheter Mitral Valve Replacement

“…Preserving the AML during surgical mitral valve replacement can cause left ventricular outflow tract (LVOT) obstruction, either when the prosthesis struts protrude into the LVOT or when a long redundant anterior leaflet prolapses into the LVOT (2,3). In a similar manner, implantation of a transcatheter heart valve (THV) inside the native or repaired mitral valve enforces an “open position” of the AML that may encroach on the LVOT (4–7). This septal displacement of the AML is exaggerated when the aortic and mitral annular planes are acutely angulated rather than parallel, when the interventricular septum bulges toward the LVOT, when the AML is elongated, and when the implant extends or flares into the left ventricle.…”