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Paravalvular leakage (PVL) occurs in 6%-15% of cases after surgical heart valve replacement. A percutaneous approach is increasingly used to close PVLs as an alternative to repeat surgery. Computed tomography (CT) can be used for simulation of fluoroscopic cardiac anatomy. This technique allows preprocedural definition of optimal C-arm angulations and PVL localization in reference to fluoroscopic views. It is very helpful for guidewire crossing of the PVL and positioning of the closure device. We report a case with the first use of dedicated software for fluoroscopic simulation (FluoroCT) in transcatheter mitral PVL closure.

Aims: Transcatheter mitral valve replacement (TMVR) is an emerging technology with the potential to treat patients with severe mitral regurgitation at excessive risk for surgical mitral valve surgery. Multimodality imaging of the mitral valvular complex and surrounding structures will be an important component for patient selection for TMVR. Our aim was to describe and evaluate a systematic multi-slice computed tomography (MSCT) image analysis methodology that provides measurements relevant for transcatheter mitral valve replacement., Methods and Results: A systematic step-by-step measurement methodology is described for structures of the mitral valvular complex including: the mitral valve annulus, left ventricle, left atrium, papillary muscles and left ventricular outflow tract. To evaluate reproducibility, two observers applied this methodology to a retrospective series of 49 cardiac MSCT scans in patients with heart failure and significant mitral regurgitation. For each of 25 geometrical metrics, we evaluated inter-observer difference and intra-class correlation. The inter-observer difference was below 10% and the intra-class correlation was above 0.81 for measurements of critical importance in the sizing of TMVR devices: the mitral valve annulus diameters, area, perimeter, the inter-trigone distance, and the aorto-mitral angle., Conclusions: MSCT can provide measurements that are important for patient selection and sizing of TMVR devices. These measurements have excellent inter-observer reproducibility in patients with functional mitral regurgitation.

Aims: Transcatheter mitral valve replacement (TMVR) is an emerging technology with the potential to treat patients with mitral regurgitation at excessive risk for mitral valve surgery. Geometrical measurements of the mitral valvular complex may have implications for the design of TMVR devices and for patient selection. This study sought to quantify the dynamic geometry of the mitral valvular complex in patients with significant functional mitral regurgitation (FMR) using multi-slice computed tomography (MSCT)., Methods and Results: MSCT images were acquired in 32 patients with symptomatic, significant FMR. Two independent observers analysed image sets using a dedicated software package and a standard measurement methodology. In patients with FMR, the mean mitral annulus intercommissural and aorto-mural diameters were, respectively, 41.5±5.2 mm and 38.7±5.9 mm in systole, and were 41.5±4.4 mm and 40.0±4.7 mm in diastole. In patients without MR, the diameters were, respectively, 33.6±5.1 mm and 28.8±8.0 mm in systole, and 36.2±4.5 mm and 31.6±7.9 mm in diastole. The obstacle-free zone below the mitral annulus averaged more than 20.0 mm and varied by less than 1 mm between systole and diastole, which is not statistically significant. The aorto-mitral angle was 129.7±10.5° in systole and 131.0±9.4° in diastole., Conclusions: The mitral annulus is larger in dimension, more circular, and less dynamic in patients with FMR. The obstacle-free zone below the mitral annulus is relatively constant during the cardiac cycle. Measurements of the mitral valvular apparatus vary considerably between patients, which suggests that tridimensional imaging will play an important role in the sizing of TMVR devices.

Background: Transcatheter interventions are currently undertaken using "generic" fluoroscopic viewing angles. However, the position and orientation of heart structures may vary across patients and disease-specific remodeling processes., Objective: This study uses multislice computed tomography to determine optimal fluoroscopic viewing angles of the aortic and mitral annuli, the left atrial appendage and the atrial septum. We explored differences between patients with severe aortic stenosis (AS) and severe mitral regurgitation (MR)., Methods and Results: The multislice computed tomographies of 28 patients with severe aortic stenosis (AS) and 32 patients with severe functional mitral regurgitation (MR) were analyzed. For each patient, we evaluated the optimal fluoroscopic viewing angles of the aortic and mitral annuli (en face, maximal and minimal diameters, aortic root with right, left and non coronary sinus in center), left atrial appendage orifice (en face, maximal and minimal diameters), and atrial septum (fossa ovalis) en face. The TAVR implantation view with right coronary sinus in center was LAO 9 - CRA 0 in the AS group and LAO 6 - CAU 5 in the MR group (p = NS). AS and MR patients differed significantly with respect to the fluoroscopic angulation of the aortic annulus en face (8.3°), the aortic annulus maximal (17.7°) and minimal (18.5°) diameters, the mitral annulus aorto-mural diameter (11.3°), and the left atrial appendage orifice en face (11.1°) (all p-values<0.05)., Conclusion: Optimal fluoroscopic viewing angles of left-sided structures vary considerably between patients. Multislice computed tomography is a valuable tool to determine the most procedurally relevant angulations, with the potential to optimize procedural safety, efficacy and duration., (Copyright © 2016 Society of Cardiovascular Computed Tomography. Published by Elsevier Inc. All rights reserved.)

Background: We sought to determine if preprocedural CT can predict appropriate fluoroscopic angulations to achieve a coplanar view during transcatheter mitral valve implantation (TMVI) and to assess the relationship of the mitral annulus and the coronary sinus to determine the feasibility of using this as an additional landmark on fluoroscopy., Methods: With CT, the mitral annulus was segmented in 25 patients with functional mitral regurgitation. After this, optimal projection curves were plotted and the necessary angulations for specific views parallel to the trigone-to-trigone line (TT view) and septal-to-lateral distance (SL view) were noted. The outer contour of the coronary sinus and great cardiac vein were segmented to simulate a guide wire, and its relation to the annular plane was assessed. Employed angulations and coplanarity of device depiction were investigated in 4 patients who underwent TMVI., Results: The mitral annulus is oriented in an anterior superior fashion with tilting to the right. SL and TT views were found at 29.4 ± 9.0° right anterior oblique (RAO), 20.1 ± 8.7° cranial (CAU) and 81.6 ± 18.9° RAO, 56.7 ± 8.0° caudal (CAU). The optimal projection curve and the relationship of coronary sinus to the mitral annular plane showed a wide intersubject variability. Commonly, the coronary sinus passed along the atrial wall with a mean distance of 13.2 ± 3.7 mm toward the mitral annular plane at P2 and 1.4 ± 3.1 mm anteriorly in alignment with the TT line. Coplanar depiction of the TMVI prosthesis was achieved in all 4 patients, with a compromise view chosen on the optimal projection curve between the TT view and SL view., Conclusion: CT allows for prediction of optimal fluoroscopic angulations to achieve a coplanar view of the mitral annulus. The relationship of the coronary sinus to the mitral annulus is variable and preprocedural CT segmentation may allow for a more patient-specific approach to the use of a coronary sinus guide wire as a fluoroscopic landmark., (Copyright © 2015 Society of Cardiovascular Computed Tomography. Published by Elsevier Inc. All rights reserved.)