1-Year Outcomes Following Transfemoral Transseptal Transcatheter Mitral Valve Replacement: Intrepid TMVR Early Feasibility Study Results

Abstract

Background: High surgical risk may preclude mitral valve replacement in many patients. Transcatheter mitral valve replacement (TMVR) using transfemoral transseptal access is a novel technology for the treatment of mitral regurgitation (MR) in high-risk surgical patients. Objectives: This analysis evaluates 30-day and 1-year outcomes of the Intrepid TMVR Early Feasibility Study in patients with ≥moderate-severe MR. Methods: The Intrepid TMVR Early Feasibility Study is a multicenter, prospective, single-arm study. Clinical events were adjudicated by a clinical events committee; endpoints were defined according to Mitral Valve Academic Research Consortium criteria. Results: A total of 33 patients, enrolled at 9 U.S. sites between February 2020 and August 2022, were included. The median age was 80 years, 63.6% of patients were men, and mean Society of Thoracic Surgeons Predicted Risk of Mortality for mitral valve replacement was 5.3%. Thirty-one (93.9%) patients were successfully implanted. Median postprocedural hospitalization length of stay was 5 days, and 87.9% of patients were discharged to home. At 30 days, there were no deaths or strokes, 8 (24.2%) patients had major vascular complications and none required surgical intervention, there were 4 cases of venous thromboembolism all successfully treated without sequelae, and 1 patient had mitral valve reintervention for severe left ventricular outflow tract obstruction. At 1 year, the Kaplan-Meier all-cause mortality rate was 6.7%, echocardiography showed ≤mild valvular MR, there was no/trace paravalvular leak in all patients, median mitral valve mean gradient was 4.6 mm Hg (Q1-Q3: 3.9-5.3 mm Hg), and 91.7% of survivors were in NYHA functional class I/II with a median 11.4-point improvement in Kansas City Cardiomyopathy Questionnaire overall summary scores. Conclusions: The early benefits of the Intrepid transfemoral transseptal TMVR system were maintained up to 1 year with low mortality, low reintervention, and near complete elimination of MR, demonstrating a favorable safety profile and durable valve function.