The various aspects of the invention pertain to devices and related methods for treating heart conditions, including, for example, dilatation, valve incompetencies, including mitral valve leakage, and other similar heart failure conditions. The devices and related methods of the present invention operate to assist in the apposition of heart valve leaflets to improve valve function. According to one aspect of the invention, a method improves the function of a valve of a heart by placing an elongate member transverse a heart chamber so that each end of the elongate member extends through a wall of the heart, and placing first and second anchoring members external the chamber. The first and second anchoring members are attached to first and second ends of the elongate member to fix the elongate member in a position across the chamber so as to reposition papillary muscles within the chamber. Also described herein is a method for placing a splint assembly transverse a heart chamber by advancing an elongate member through vasculature structure and into the heart chamber.