Russell, Hyde M.

Introduction: Transcatheter mitral valve replacement (TMVR) using aortic transcatheter heart valves (THV) is developing as an alternative to surgery for patients with severely degenerated mitral valve (MV) bioprostheses. Retrospective self-reported registries have collected outcomes on these TMVR procedures in the STS/ACC Transcatheter Valve Therapy Registry and in the Valve-in-Valve International Database. Most reported TMVR procedures for failed surgical bioprostheses have been performed using a transapical access approach. A prospective comprehensive evaluation of mitral Valve-in-Valve (VIV) outcomes, including transseptal access has not previously been conducted. Objectives: To evaluate in-hospital and 30-day clinical outcomes of transseptal mitral VIV with SAPIEN 3 THV in patients with very high surgical risk. Methods: Prospective enrollment of very high surgical risk patients with symptomatic severely degenerated MV surgical bioprostheses in 30 patients at 15 sites in the U.S. Candidates were assessed by a case review committee prior to approval. Baseline qualifying echocardiograms and cardiac CT studies were analyzed by independent core labs. Echocardiograms, cardiac CT studies and neurology evaluations were also performed after mitral VIV procedures. Clinical events were adjudicated by a clinical events committee and safety was monitored by a data safety monitoring board. Results: 26 patients have been enrolled between July 2016 and June 2017. Mean age was 83 years, 62% female, mean STS score was 10% and 62% were in New York Heart Association class III or IV. Transseptal access was used in all procedures. Technical success was achieved in all patients and there was no in-hospital mortality. There was no 30-day cardiovascular mortality and 4% (1 patient) 30-day all-cause mortality (1 patient died of asphyxia on day 29 after choking on pills at home), which was lower than the 30-day mortality in the TVT registry (9%). Detailed procedural, in-hospital and 30-day outcomes will be presented on the complete cohort of 30 patients. Conclusions: In patients without surgical alternatives, transseptal mitral ViV procedures in failed surgical bioprostheses are associated with high technical and procedural success and low 30-day mortality.

Background: Transcatheter mitral valve replacement using aortic transcatheter heart valves has recently become an alternative for patients with degenerated mitral bioprostheses, failed surgical repairs with annuloplasty rings or severe mitral annular calcification who are poor surgical candidates. Outcomes of these procedures are collected in the Society of Thoracic Surgeons/American College of Cardiology/Transcatheter Valve Therapy Registry. A comprehensive analysis of mitral valve-in-valve (MViV), mitral valve-in-ring (MViR), and valve-in-mitral annular calcification (ViMAC) outcomes has not been performed. We sought to evaluate short-term outcomes of early experience with MViV, MViR, and ViMAC in the United States. Methods: Retrospective analysis of data from the Society of Thoracic Surgeons/American College of Cardiology Transcatheter Valve Therapy Registry. Results: Nine hundred three high-risk patients (median Society of Thoracic Surgeons score 10%) underwent MViV (n=680), MViR (n=123), or ViMAC (n=100) between March 2013 and June 2017 at 172 hospitals. Median age was 75 years, 59.2% female. Technical and procedural success were higher in MViV. Left ventricular outflow tract obstruction occurred more frequently with ViMAC (ViMAC=10%, MViR=4.9%, MViV=0.7%; P <0.001). In-hospital mortality (MViV=6.3%, MViR=9%, ViMAC=18%; P =0.004) and 30-day mortality (MViV=8.1%, MViR=11.5%, ViMAC=21.8%; P =0.003) were higher in ViMAC. At 30-day follow-up, median mean mitral valve gradient was 7 mm Hg, most patients (96.7%) had mitral regurgitation grade ≤1 (+) and were in New York Heart Association class I to II (81.7%). Conclusions: MViV using aortic balloon-expandable transcatheter heart valves is associated with a low complication rate, a 30-day mortality lower than predicted by the Society of Thoracic Surgeons score, and superior short-term outcomes than MViR and ViMAC. At 30 days, patients in all groups experienced improvement of symptoms, and valve performance remained stable. Registration: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT02245763.

Abstract Aims To investigate valve sizing and the haemodynamic relevance of the predicted left ventricular outflow tract (LVOT) in patients with mitral annular calcification (MAC) undergoing transatrial transcatheter valve implantation (THV). Methods and results In total, 21 patients undergoing transatrial THV, multiplanar reconstruction (MPR), maximum intensity projection (MIP), and cubic spline interpolation (CSI) were compared for MA sizing during diastole. In addition, predicted neo-LVOT areas were measured in 18 patients and correlated with the post-procedural haemodynamic dimensions. The procedure was successful in all patients (100%). Concomitant aortic valve replacement was performed in eight patients (43%) (AVR group). Sizing using MPR and MIP yielded comparable results in terms of area, perimeter, and diameter, whereas the dimensions obtained with CSI were systematically smaller. The simulated mean systolic neo-LVOT area was 133.4 ± 64.2 mm2 with an anticipated relative LVOT area reduction (neo-LVOT area/LVOT area × 100) of 59.3 ± 14.7%. The systolic relative LVOT area reduction, but not the absolute neo-LVOT area, was found to predict the peak (r = 0.69; P = 0.002) and mean (r = 0.65; P = 0.004) post-operative aortic gradient in the overall population as well as separately in the AVR (peak: r = 0.91; P = 0.002/mean: r = 0.85; P = 0.002) and no-AVR (peak: r = 0.89; P = 0.003/mean: r = 0.72; P = 0.008) groups. Conclusion In patients with severe MAC undergoing transatrial transcatheter valve implantation, MPR, and MIP yielded comparable annular dimensions, while values obtained with CSI tended to be systematically smaller. Mitral annular area and the average annular diameter appear to be reliable parameters for valve selection. Simulated relative LVOT reduction was found to predict the post-procedural aortic gradients.