Multimodality Cardiac Imaging for Procedural Planning and Guidance of Transcatheter Mitral Valve Replacement and Mitral Paravalvular Leak Closure

Figures

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  Figure 1. Quantification of mitral regurgitation (MR). (A) Calculation of effective regurgitant orifice area (EROA) and regurgitant volume (RVol) by proximal isovelocity surface area (PISA) method. Indicators for severe MR include elevated early diastolic mitral inflow (E wave) velocity (B), dense continuous-wave Doppler signal (C), and systolic reversal of pulmonary vein flow (D). (E) 3D vena contracta area reconciles discrepant linear vena contracta width measurements in an elliptical regurgitant orifice. (F) With cardiac MRI, mitral RVol is calculated as the difference between total left ventricular stroke volume and the aortic flow (forward stroke volume) by phase-contrast imaging.

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  Figure 2. Paravalvular mitral regurgitation assessment by TEE. (A) 3D en face “surgeon's view” of a mitral bioprosthesis demonstrates a gap along the posteromedial aspect, corresponding to a paravalvular defect. (B) Rotation of the 3D volume improves visualization of the paravalvular defect. (C) Color Doppler confirms regurgitant flow through the defect and no other areas of paravalvular leak (PVL). Sizing of PVL by TEE can be difficult due to irregularity in the shape of the defect and dropout artifact, as shown in (D), and is best measured with color Doppler to delineate the regurgitant PVL jet and avoid overestimation (E).

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  Figure 3. CT annular segmentation for TMVR. (A–D) Segmentation of the native mitral annulus for the planning of valve-in-MAC TMVR. As shown from a long-axis view (A), the mitral annulus outlined in red (A) has a non-planar saddle geometry. Projected into a short-axis view (B), the anterior horn (pink border) may be truncated to assume a D-shaped configuration. (C) The trigone-trigone (orange), septal-lateral (blue), and inter-commissural (white) distances are measured from this view. Maximum intensity projection (D) allows for assessment of the distribution and density of annular calcification. (E) Valve-in-ring TMVR measurements of a complete semi-rigid ring with the major diameter in the inter-commissural dimension (red) and the minor diameter in the septal-lateral dimension (orange). (F) Valve-in-valve TMVR assessment showing the internal diameter slightly under the manufacturer specifications for the bioprosthesis.

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  Figure 4. Evaluation of predicted neo-LVOT area by CT. (A–D) LVOT assessment for valve-in-MAC TMVR. Virtual implantation of a cylindrical transcatheter valve coaxial to the mitral annulus during a systolic phase (A) and delineation of the LVOT centerline yields a short-axis view of the predicted neo-LVOT area (B, orange), which measures 2.66 cm2 and predicts a low risk of LVOT obstruction with TMVR in this case. (E) Volume rendered image showing a capacious neo-LVOT area in a case under consideration for valve-in-ring TMVR.

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  Figure 5. CCTA-based Fluoroscopic Simulation for TMVR access planning. Projected Fluoroscopic coplanar angles can be found along the displayed S-curve. A coplanar working view (A) and modified 4-chamber view (B) are displayed for a planned valve-in-ring procedure. (C) Full transseptal access planning is shown, with a projected catheter path through the IVC (turquoise cylinder) and across the interatrial septum for coaxial valve implantation from the working view. Catheter bend angle is displayed (85 degrees) and ideal entry distance from the mitral annulus (27.3 mm).

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  Figure 6. Trans-septal puncture and septostomy for TMVR. A transseptal needle is seen tenting the interatrial septum (red arrows), best assessed utilizing biplane TEE imaging in the bi-caval (superior-inferior, A) and short-axis (anterior-posterior, B) views to confirm positioning in the inferior and posterior aspect of the fossa ovalis. After a successful transseptal puncture, a balloon is advanced over a stiff wire, and proper positioning across the septum can be verified utilizing live 3D MPR (C,D). (E) The balloon is visualized in a 3D zoom volume-rendered image from the left atrial perspective. (F) The balloon is inflated for atrial septostomy in order to later accommodate the large crimped TMVR device. Supplementary Video 1 illustrates balloon inflation for atrial septostomy, as seen from the left atrium.

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  Figure 7. Fusion Imaging. 2 PVL jets are seen on TEE color Doppler imaging in a patient who had previously undergoing TAVR (A). These were anatomically located on subsequent CCTA (B,C, red arrows) and co-registered onto fluoroscopic procedural imaging (D, yellow and green circles). (E) A mitral PVL closure using live TEE fusion imaging for co-localization.

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  Figure 8. TMVR device positioning. As the orientation of the device may differ from that of the ultrasound plane, live TEE 3D MPR is helpful to properly assess positioning in regards to a calcified mitral annulus (ViMAC) or prior surgical ring (ViR) (A,B). Valve deployment can also be visualized in an en-face surgeon's view (C,D, see Supplementary Video 2). In the case of a valve in valve implantation, a 26 mm Sapien S3 valve is seen being positioned inside a 29 mm bioprosthetic surgical valve in 3D MPR (E,F), confirming alignment of the ventricular edge of the THV valve frame with the ventricular edge of the existing bioprosthesis which can be identified in fluoroscopy (G, red arrows). During deployment (H), the THV shortens predominantly from the inflow (atrial) side, leading to its final position. Supplementary Video 2 demonstrates THV deployment in live 3D MPR.

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  Figure 9. LAMPOON procedure during TMVR. In cases of anticipated LVOT obstruction, intentional laceration of the anterior mitral valve leaflet (LAMPOON procedure) can be performed by connecting a retrograde wire through the aortic valve and an antegrade transseptal wire from the LA to form a loop via snaring (A). The loop is positioned in the trajectory to transect the A2 scallop (B), and tension is applied during radiofrequency energy application to lacerate the anterior leaflet from base to tip (C). In this case, post-valve-in-ring implantation measurement demonstrated a mean gradient across the LVOT of 10 mm Hg (D).

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  Figure 10. Post TMVR assessment immediately after deployment. (A) 3D color Doppler evaluation from an en-face surgeon's view immediately after a valve in MAC implantation reveals two areas of paravalvular leak (PVL) at 10 and 1 o'clock (yellow arrows). See Supplementary Video 3 for 3D en face evaluation of valve morphology and leaflet motion. (B) Careful interrogation of the largest area of PVL with 3D MPR reveals a vena contracta area of 0.12 cm2. (C) Pulsed-wave Doppler interrogation of the LVOT from a transgastric view in order to exclude a significant gradient or obstruction. (D) Evaluation of residual iatrogenic septal defect size and direction of flow.

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  Figure 11. TEE Guidance of Challenging Closure of Posteromedial PVL. A posterior paravalvular leak resulting in hemolysis is visualized by 2D color Doppler (A) and 3D color Doppler Imaging (between 5 and 6 o clock in a surgeon's view, red arrow, B). (C) The first attempt at transseptal puncture is shown (green circle). The location of PVL is marked by a red circle. (D) After unsuccessful attempts to cross the defect, the septum was repunctured more posterior (green circle) for a better trajectory toward the defect. (E) After additional unsuccessful attempts, the approach was changed to retrograde. (F) As acoustic shadowing limits visualization on the ventricular aspect of the mechanical mitral prosthesis, wire exit point was visualized in the left atrium. Here, the wire is visualized inside the sewing ring (red arrow) adjacent to the PVL (red circle). (G) After reorientation of the wire, the defect was successfully crossed (red arrow). (H) The atrial disk of an AVPII closure device is visualized after deployment on 3D imaging (red arrow). (I) 2D echocardiography demonstrates the atrial disk (red arrow) and a portion of the center cylinder (yellow arrow). (J) A residual peri-device jet is…

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  Figure 12. TEE Guided Implantation of a Second PVL Closure Device for Residual Leak. (A) After an initial deployment of a 10 mm AVPII device, a residual leak is seen adjacent to the first device (red arrow). (B) A sector-based 3D Color Doppler acquisition demonstrates the location of the residual leak medial to the first device. (C) Multiplanar reconstruction of the 3D color Doppler acquisition is aligned with the jet for measurement of the paravalvular defect (lower left panel, dotted red tracing), measuring 17 mm2, with dimensions 10 x 4 mm. (D) The guide catheter is positioned on top of the first device, too lateral to enter the defect. (E) The guide is pulled back, and wire crossing of the defect (red circle) is attempted. Wire trajectory is medial and anterior to the defect. (F) After correction of wire trajectory, the defect is crossed. (G) A 12 mm AVPII device is deployed within the residual defect. (H) Bioprosthetic leaflet opening appears normal, without interference from the closure devices. (I) Biplane color Doppler imaging demonstrates trivial residual leak after deployment of the 2nd PVL closure device.