Pascal Thériault-Lauzier

Transcatheter aortic valve replacement in bicuspid aortic valve disease.

BACKGROUND Limited information exists describing the results of transcatheter aortic valve (TAV) replacement in patients with bicuspid aortic valve (BAV) disease (TAV-in-BAV). OBJECTIVES This study sought to evaluate clinical outcomes of a large cohort of patients undergoing TAV-in-BAV. METHODS We retrospectively collected baseline characteristics, procedural data, and clinical follow-up findings from 12 centers in Europe and Canada that had performed TAV-in-BAV. RESULTS A total of 139 patients underwent TAV-in-BAV with the balloon-expandable transcatheter heart valve (THV) (n = 48) or self-expandable THV (n = 91) systems. Patient mean age and Society of Thoracic Surgeons predicted risk of mortality scores were 78.0 ± 8.9 years and 4.9 ± 3.4%, respectively. BAV stenosis occurred in 65.5%, regurgitation in 0.7%, and mixed disease in 33.8% of patients. Incidence of type 0 BAV was 26.7%; type 1 BAV was 68.3%; and type 2 BAV was 5.0%. Multislice computed tomography (MSCT)-based TAV sizing was used in 63.5% of patients (77.1% balloon-expandable THV vs. 56.0% self-expandable THV, p = 0.02). Procedural mortality was 3.6%, with TAV embolization in 2.2% and conversion to surgery in 2.2%. The mean aortic gradient decreased from 48.7 ± 16.5 mm Hg to 11.4 ± 9.9 mm Hg (p < 0.0001). Post-implantation aortic regurgitation (AR) grade ≥ 2 occurred in 28.4% (19.6% balloon-expandable THV vs. 32.2% self-expandable THV, p = 0.11) but was prevalent in only 17.4% when MSCT-based TAV sizing was performed (16.7% balloon-expandable THV vs. 17.6% self-expandable THV, p = 0.99). MSCT sizing was associated with reduced AR on multivariate analysis (odds ratio [OR]: 0.19, 95% confidence intervals [CI]: 0.08 to 0.45; p < 0.0001). Thirty-day device safety, success, and efficacy were noted in 79.1%, 89.9%, and 84.9% of patients, respectively. One-year mortality was 17.5%. Major vascular complications were associated with increased 1-year mortality (OR: 5.66, 95% CI: 1.21 to 26.43; p = 0.03). CONCLUSIONS TAV-in-BAV is feasible with encouraging short- and intermediate-term clinical outcomes. Importantly, a high incidence of post-implantation AR is observed, which appears to be mitigated by MSCT-based TAV sizing. Given the suboptimal echocardiographic results, further study is required to evaluate long-term efficacy.

Transcatheter heart valve failure: a systematic review

AIMS A comprehensive description of transcatheter heart valve (THV) failure has not been performed. We undertook a systematic review to investigate the aetiology, diagnosis, management, and outcomes of THV failure. METHODS AND RESULTS The systematic review was performed in accordance with the PRISMA guidelines using EMBASE, MEDLINE, and Scopus. Between December 2002 and March 2014, 70 publications reported 87 individual cases of transcatheter aortic valve implantation (TAVI) failure. Similar to surgical bioprosthetic heart valve failure, we observed cases of prosthetic valve endocarditis (PVE) (n = 34), structural valve failure (n = 13), and THV thrombosis (n = 15). The microbiological profile of THV PVE was similar to surgical PVE, though one-quarter had satellite mitral valve endocarditis, and surgical intervention was required in 40% (75% survival). Structural valve failure occurred most frequently due to leaflet calcification and was predominantly treated by redo-THV (60%). Transcatheter heart valve thrombosis occurred at a mean 9 ± 7 months post-implantation and was successfully treated by prolonged anticoagulation in three-quarters of cases. Two novel causes of THV failure were identified: late THV embolization (n = 18); and THV compression (n = 7) following cardiopulmonary resuscitation (CPR). These failure modes have not been reported in the surgical literature. Potential risk factors for late THV embolization include low prosthesis implantation, THV undersizing/underexpansion, bicuspid, and non-calcified anatomy. Transcatheter heart valve embolization mandated surgery in 80% of patients. Transcatheter heart valve compression was noted at post-mortem in most cases. CONCLUSION Transcatheter heart valves are susceptible to failure modes typical to those of surgical bioprostheses and unique to their specific design. Transcatheter heart valve compression and late embolization represent complications previously unreported in the surgical literature.

TRANSCATHETER HEART VALVE FAILURE: A SYSTEMATIC REVIEW

No study has addressed the failure modes of transcatheter heart valves (THV). We performed a systematic review to investigate the causes of THV failure, and to describe the clinical characteristics, diagnosis, management, and outcomes of these patients. Between January 2002 and October 2013, all

Predicting LVOT Obstruction in Transcatheter Mitral Valve Implantation: Concept of the Neo-LVOT

Outflow tract obstruction is a feared and potentially lethal complication of transcatheter mitral valve replacement (TMVR), mitral valve-in-valve (ViV), and valve-in-ring (ViR) procedures as well as implantation of transcatheter heart valves in calcific mitral valve disease. These procedures

Prediction of fluoroscopic angulation and coronary sinus location by CT in the context of transcatheter mitral valve implantation

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.

Fluoroscopic anatomy of left-sided heart structures for transcatheter interventions: insight from multislice computed tomography.

With the introduction of transcatheter structural heart therapies, cardiologists are increasingly aware of the importance of understanding anatomical details of left-sided heart structures. Understanding fluoroscopic cardiac anatomy can facilitate optimal positioning and deployment of prostheses during transcatheter valve repair/replacement, left atrial appendage occlusion, septal defect closure, and paravalvular leak closure. It is possible to use multislice computed tomography to determine optimal fluoroscopic viewing angles for such transcatheter therapies. The purpose of this paper is to describe how optimal fluoroscopic viewing angles of left-sided heart structures can be obtained using computed tomography. Two- and 3-chamber views are described and may become standard in the context of transcatheter structural heart interventions.

Quantitative multi-slice computed tomography assessment of the mitral valvular complex for transcatheter mitral valve interventions part 1: systematic measurement methodology and inter-observer variability.

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.

Quantitative multi-slice computed tomography assessment of the mitral valvular complex for transcatheter mitral valve interventions part 2: geometrical measurements 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.

Transcatheter aortic valve implantation versus redo surgery for failing surgical aortic bioprostheses: a multicentre propensity score analysis

AIMS Transcatheter aortic valve implantation for a failing surgical bioprosthesis (TAV-in-SAV) has become an alternative for patients at high risk for redo surgical aortic valve replacement (redo-SAVR). Comparisons between these approaches are non-existent. This study aimed to compare clinical and echocardiographic outcomes of patients undergoing TAV-in-SAV versus redo-SAVR after accounting for baseline differences by propensity score matching. METHODS AND RESULTS Patients from seven centres in Europe and Canada who had undergone either TAV-in-SAV (n=79) or redo-SAVR (n=126) were identified. Significant independent predictors used for propensity scoring were age, NYHA functional class, number of prior cardiac surgeries, urgent procedure, pulmonary hypertension, and COPD grade. Using a calliper range of ±0.05, a total of 78 well-matched patient pairs were found. All-cause mortality was similar between groups at 30 days (6.4% redo-SAVR vs. 3.9% TAV-in-SAV; p=0.49) and one year (13.1% redo-SAVR vs. 12.3% TAV-in-SAV; p=0.80). Both groups also showed similar incidences of stroke (0% redo-SAVR vs. 1.3% TAV-in-SAV; p=1.0) and new pacemaker implantation (10.3% redo-SAVR vs. 10.3% TAV-in-SAV; p=1.0). The incidence of acute kidney injury requiring dialysis was numerically lower in the TAV-in-SAV group (11.5% redo-SAVR vs. 3.8% TAV-in-SAV; p=0.13). The TAV-in-SAV group had a significantly shorter median total hospital stay (12 days redo-SAVR vs. 9 days TAV-in-SAV; p=0.001). CONCLUSIONS Patients with aortic bioprosthesis failure treated with either redo-SAVR or TAV-in-SAV have similar 30-day and one-year clinical outcomes.

Measurements matters: the case for 3D MSCT software for aortic annulus quantification.

Up until 2010, paravalvular aortic regurgitation (pAR) of any severity was diagnosed in 70-90% of patients after transcatheter aortic valve implantation (TAVI) using either a selfor balloonexpanding prosthesis; moderate to severe pAR was observed in 10-30%1. During the last two years, moderate to severe pAR has been documented in 0-12% of patients undergoing TAVI (Figure 1), including those patients implanted with the Medtronic CoreValve (Medtronic, Minneapolis, MN, USA), a valve which has not undergone significant iterations until recently. What can explain the significant reductions in pAR over time? From the first TAVI in 2002 to 2010, two-dimensional (2D) echocardiography was the gold standard imaging modality for transcatheter aortic valve sizing. In the last two years, we have witnessed a rapid and dramatic shift to multislice computed tomography (MSCT)-based transcatheter aortic valve sizing. Amongst other less influential factors, this shift to MSCT appears to explain the significant reductions in pAR over time. Although randomised comparisons are lacking, observational studies strongly suggest