Transcatheter mitral valve replacement with the NaviGate stent in a preclinical model

Abstract

Aims: The aim of this study was to test the feasibility of transcatheter mitral valve implantation of the NaviGate device in acute and chronic preclinical models.

Methods and results: We evaluated NaviGate valved stent implantation in the mitral position in an acute swine model (n = 24, <= 5 days) through three different approaches - transatrial, transapical, and transseptal - and in a chronic swine model (n = 12, > 10 days) through a transatrial approach. The NaviGate implantation procedures were successful in 83% of the acute model studies (n = 20) and 83% of the chronic model studies (n = 10). Echocardiographic assessment showed low gradient across the valved stent (mean gradient < 3 mmHg) and the left ventricular outflow tract (mean gradient < 6 mmHg). Post implantation, there was no mitral regurgitation (MR) in 75% (n = 15) of the acute studies and mild MR in 25% (n = 5). In the chronic model, there was no MR in 60% (n = 6) and mild MR in 40% (n = 4). The implantation procedure was aborted in four acute studies due to inferior vena cava injury and in two chronic studies due to prosthesis-annulus mismatch