Transcatheter Mitral Valve Implantation: 30-day Outcome of First-in-Man Experience with an Apically Tethered Device

Abstract

Objective

A small number of transcatheter mitral valve implants (TMVIs) have been reported using devices designed to treat secondary mitral regurgitation (MR). However, MR has many etiologies, and patients have a broad spectrum of annular size, geometry, and lesions. There are a number of technical challenges for TMVI including left ventricular outflow tract obstruction and paravalvular MR. Thirty days’ outcome of first-in-man implants with a novel TMVI device is reported.

Methods

The Tendyne TMVI system consists of a porcine pericardial valve in a tethered nitinol frame. An apical tether fixed to an epicardial pad stabilizes the device. The device is fully repositionable and retrievable even after complete deployment. Preoperative assessment was performed with 3-dimensional (3D) transesophageal echocardiogram and multislice computed tomography to define annular dimensions, geometry, and guide surgical access. Three patients were deemed not to be candidates for conventional surgery or for treatment with any Conformitè Européenne-marked device by Heart Team Evaluation. They were a 68-year-old woman with prior coronary artery bypass grafts and severe functional MR; a 75-year-old man with prior coronary bypass grafts, significant renal dysfunction, and severe degenerative MR; and a frail 86-year-old man with severe degenerative MR. Each had a TMVI via a transapical approach through a left minithoracotomy. Apical tether tension was adjusted to optimize device position.

Results

Implantation was guided by 2D and 3D transesophageal echocardiogram. The apical pad facilitated LV apical closure. There were no procedural complications. No patient had hemodynamically significant residual MR or left ventricular outflow tract obstruction, and there was no significant mitral gradient. All patients were discharged to their own home (the third on the fifth postoperative day), all with significant improvement in their symptoms. All were alive and well 30 days after implant. Two patients with existing conduction abnormalities had cardiac resynchronisation therapy after the procedure, and one patient had para valvular leak (PVL) with evidence of hemolysis at 30 days, which reduced in severity with conservative treatment.

Conclusions

The first-in-man experience with the Tendyne TMVI system is promising. Valve stabilization by an apical tether is a novel way to address some of the challenges of TMVI. The unique Tendyne design features may offer potential for its use across a wide range of mitral valve pathologies.