Malaisrie SC, Guerrero M, Davidson C, Williams M, de Brito FS Jr, Abizaid A, Shah P, Kaneko T, Poon K, Levisay J, Yu X, Pibarot P, Hahn RT, Blanke P, Leon MB, Mack MJ, and Zajarias A
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., Competing Interests: Dr Malaisrie reports institutional research grants from Edwards Lifesciences, Medtronic, and Terumo Medical Corporation and consulting/speaker fees from Edwards Lifesciences, Terumo Medical Corporation, and Artivion; Dr Guerrero reports institutional research grants from Edwards Lifesciences; Dr Davidson reports institutional research grants from Edwards Lifesciences and Abbott Vascular and consulting/speaker fees from Edwards Lifesciences; Dr Williams reports institutional research grants from Edwards Lifesciences, Abbott Vascular, Medtronic, and Boston Scientific and consulting/speaker fees from Medtronic; Dr de Brito is a proctor for Medtronic, Edwards Lifesciences, and Boston Scientific; Dr Shah reports institutional research grants from Edwards Lifesciences, Medtronic, and Abbott Vascular and consulting/speaker fees from Edwards Lifesciences; Dr Kaneko reports consulting/speaker fees from Edwards Lifesciences, Medtronic, and Abbott Vascular; Dr Poon reports institutional research grants from Edwards Lifesciences and consulting/speaker fees from Edwards Lifesciences and Anteris; Dr Yu is an employee of Edwards Lifesciences; Dr Pibarot reports institutional research grants from Edwards Lifesciences, Medtronic, Pi-Cardia, and Cardiac Success; Dr Hahn reports speaker fees from Abbott Structural, Baylis Medical, Edwards Lifesciences, Medtronic, and Philips Healthcare; she has institutional consulting contracts for which she receives no direct compensation with Abbott Structural, Edwards Lifesciences, Medtronic and Novartis; she is Chief Scientific Officer for the Echocardiography Core Laboratory at the Cardiovascular Research Foundation for multiple industry-sponsored tricuspid valve trials, for which she receives no direct industry compensation; Dr Blanke reports consulting/speaker fees from Edwards Lifesciences and LARALAB; Dr Leon reports institutional research grants from Edwards Lifesciences, Medtronic, Boston Scientific, and Abbott Vascular; Dr Mack has served as trial coprimary investigator for Edwards Lifesciences and Abbott Vascular and has served as a study chair for Medtronic; Dr Zajarias reports consulting/speaker fees from Edwards Lifesciences and Medtronic. The other authors report no conflicts.