LV unloading and RV remodeling:
LV chamber dilatation, in association with residual or uncorrected MR, increases the pericardial constraints on the right ventricle and impairs RV contractile performance [21]. Following surgical MV repair, a reduction in LV volumes has been associated with an improvement in RV function [3]. As has previously been reported, our data demonstrated that Tendyne TMVI resulted in an abolition of MR and a significant reduction in LV volumes [12, 13]. TMVI induced LV unloading was maximal in the period immediately following implantation, however a gradual re-dilatation of the left ventricle was observed in those patients with severe pre-existing LV dysfunction (Table 5; Figures 4 and 5). We also observed a post-operative reduction in LVEF which is consistent with what has previously been described in surgical and transcatheter repair studies due to the unmasking of the true intrinsic myocardial function of the volume-loaded LV through elimination of MR. Regardless, the abolition of MR and concomitant reduction in LV volumes, resulted in an immediate and sustained improvement in RV function as determined invasively post-deployment by RVSWI and non-invasively by RVFAC on echocardiography (p<0.001; Table 4 and Figure 3). The improvement in RV function was seen both in patients with moderate (p=0.02) and severe (p=0.02) LV dysfunction.