Aims: The haemodynamic effect of mitral valve (MV) repair using multiple MitraClips® (MC) has not been investigated. The aim of the study was to evaluate the stress performance of MV repair with MC.
Methods and results: Twenty consecutive patients (77±7 years, 13 men [65%]) after implantation of >2 MitraClips® were subsequently evaluated with dobutamine stress echocardiography (DSE). After MC implantation, mean transmitral pressure gradient (TPG) (3.3±0.8 mmHg vs. 4.0±0.6 mmHg; p<0.001) and mitral valve orifice area (2.9±0.3 cm2 vs. 3.9±0.4 cm2; p<0.001) were significantly increased during DSE showing a physiological behaviour effect of the MV. LVEF (41±18% vs. 46±21%; p<0.001) and systolic pulmonary artery pressure (42±11 mmHg vs. 44±12 mmHg; p=0.014) increased significantly. The degree of MR was stable during stress (p=0.68). At linear regression, only baseline peak TPG was related to stress mean TPG (p<0.001; Beta 0.816; 95% CI: 0.368-0.918).
Conclusions: MV repair using MitraClips® should be performed with the aim of maximal reduction of MR degree. MV repair using MC may not lead to pathological degrees of MV stenosis. Although the TPG is significantly increased during stress, it never reaches pathological levels and is always accompanied by a significant increase in MVOA. The degree of residual MR remains unchanged during maximal pharmacological stress.