A system for treating mitral valve regurgitation includes a tensioning device having a plurality of helical anchors and a tensioning filament. One embodiment of the invention includes a method for attaching a tensioning device to the annulus of a mitral valve in a trans-leaflet configuration, and applying a tension force to the tension filament in order to exert force vectors on the annulus, thereby reshaping the mitral valve annulus so that the coaption of the anterior and posterior leaflets of the mitral is improved during ventricular contraction.