A method and apparatus for performing mitral valve chordal repair on a patient include attaching at least one filament to a mitral valve leaflet and to a papillary muscle. 5 to 10 mol in terms of SiO2 and at least one member selected from permanganates of Mg, Sr, Zn, Ba, and Ca in a proportion of 0. Axial conductors may be provided extending from the arrays and toward each other in order to increase the heating of tissues lying along the axis between the deployed electrode arrays.