Kaneko, Tsuyoshi

BACKGROUND: Transcatheter mitral valve-in-valve replacement offers a less-invasive alternative for high-risk patients with bioprosthetic valve failure. Limited experience exists in intermediate-risk patients. We aim to evaluate 1-year outcomes of the PARTNER 3 mitral valve-in-valve study. METHODS: This prospective, single-arm, multicenter study enrolled symptomatic patients with a failing mitral bioprosthesis demonstrating greater than or equal to moderate stenosis and regurgitation and Society of Thoracic Surgeons score ≥3% and <8%. A balloon-expandable transcatheter heart valve (SAPIEN 3, Edwards Lifesciences) was used via a transeptal approach. The primary end point was the composite of all-cause mortality and stroke at 1 year. RESULTS: A total of 50 patients from 12 sites underwent mitral valve-in-valve from 2018 to 2021. The mean age was 70.1±9.7 years, mean Society of Thoracic Surgeons score was 4.1%±1.6%, and 54% were female. There were no primary end point events (mortality or stroke) through 1 year, and no left-ventricular outflow tract obstruction, endocarditis, or mitral valve reintervention was reported. Six patients (12%) required rehospitalization, including heart failure (n=2), minor procedural side effects (n=2), and valve thrombosis (n=2; both resolved with anticoagulation). An additional valve thrombosis was associated with no significant clinical sequelae. From baseline to 1 year, all subjects with available data had none/trace or mild (grade 1+) mitral regurgitation and the New York Heart Association class improved in 87.2% (41/47) of patients. CONCLUSIONS: Mitral valve-in-valve with a balloon-expandable valve via transseptal approach in intermediate-risk patients was associated with improved symptoms and quality of life, adequate transcatheter valve performance, and no mortality or stroke at 1-year follow-up. REGISTRATION: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT03193801.

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.