Different indicators for postprocedural mitral stenosis caused by single- or multiple-clip implantation after percutaneous mitral valve repair

Abstract

BackgroundPostprocedural mitral stenosis (MS) is a main limitation for MitraClip™ (Abbot Vascular, Inc., Santa Clara, CA, USA) procedure. The purpose of this study was to detect the preprocedural predictors of high transmitral pressure gradient (TMPG) after MitraClip™ implantation, which indicated postprocedural mitral stenosis (MS). MethodsWe studied 79 patients who were implanted with MitraClip™ in our institute. Before the procedure, mitral valve orifice area (MVOA), and anterior–posterior (AP) and medial-lateral (ML) mitral annular diameters were measured at diastole using three-dimensional (3D) transesophageal echocardiography (TEE) data set. After the procedure, the mean TMPG was assessed using continuous-wave (CW) Doppler by periprocedural TEE. ResultsPreprocedural MVOA, and AP and ML diameter of left ventricular (LV) inflow orifices were larger in patients with mean TMPG ≤4mmHg than in patients with TMPG >4mmHg after 1-and 2-clip implantation. The large MVOA and ML diameter of LV inflow orifice strongly correlated with the low TMPG after 1- and 2-clip implantation. As a result of the receiver operating characteristic curve analysis, the preprocedural MVOA predicted the low postprocedural TMPG more accurately than the ML diameter of LV inflow orifice after 1-clip implantation either in the degenerative or functional mitral regurgitation (MR) patients. After 2-clip implantation, however, the preprocedural ML diameter of LV inflow orifice predicted it more accurately than the MVOA in the degenerative and functional MR patients. Conclusions3D TEE derived MVOA predicts the postprocedural MS after 1-clip implantation, however, preprocedural ML diameter of LV inflow orifice is more useful to predict after 2-clip implantation.