Transcatheter mitral valve replacement with Mi‐thos system: First‐in‐human experience

Abstract

Background Transcatheter mitral valve replacement (TMVR) has become an alternative for high‐risk patients with severe mitral regurgitation (MR). The aim of this study was to evaluate the safety and feasibility of the Mi‐thos TMVR system (NewMed Medical) for high‐risk patients with severe MR.
Methods This was a prospective, two‐center, single‐arm early feasibility study. Baseline characteristics, procedural data and 30‐day follow‐up outcomes were collected and analyzed. The primary endpoint was intraoperative success rate of device implantation. The second endpoints were all‐cause mortality and major post‐procedural complications. Echocardiographic data were evaluated by an independent core laboratory. Clinical events were adjudicated by a clinical events committee.
Results Ten high‐risk patients with severe MR were enrolled at two sites from August 2021 to November 2022. The median age was 70.5 years, and 60% of patients were female. The median Society of Thoracic Surgeons Predicted Risk of Mortality was 9.5%. The Mi‐thos TMVR system was successfully implanted via transapical access in all patients. There was no pericedural mortality or major postpericedural complications during the 30‐day follow‐up. All implanted prosthetic valves had no or trace valvular or paravalvular MR, and the median mitral valve gradient at 30 days was 2.0 mmHg (IQR: 2.0–3.0 mmHg). There was one mild left ventricular outflow tract obstruction.
Conclusions The favorable short‐term outcomes of the Mi‐thos TMVR system demonstrated that it might be a feasible and safe therapeutic alternative for high‐risk patients with severe MR. Nevertheless, further evaluation of the Mi‐thos TMVR system is warranted.

Keywords: first‐in‐human; Mi‐thos valve; mitral regurgitation; transcatheter mitral valve replacement.