A method for placing a splint assembly transverse a heart chamber includes providing an elongate member having a first end and a second end and a deployable heart-engaging assembly connected to at least the first end. The method includes advancing the elongate member through vasculature structure and into the heart chamber such that the first end of the elongate member extends through a first location of a wall surrounding the heart chamber and the second end extends through a second location of the heart chamber wall substantially opposite the first location. A deployable heart-engaging assembly is deployed such that it engages with a first exterior surface portion of the heart chamber wall adjacent the first location. The elongate member is secured with respect to the heart with a second heart-engaging assembly connected to the second end. The second heart-engaging assembly engages with a second exterior surface portion of the heart chamber wall adjacent the second location. A splint assembly includes an expandable heart-engaging assembly formed partially from portions forming the elongate member of the splint assembly. A delivery tool includes a tubular member configured to be advanced through vasculature structure and has a curved distal end.