A system for treating a heart, the heart having a right ventricle and a left ventricle with a septum there between, the system comprising: a first elongate shaft having a proximal end and a distal end, the distal end of the first elongate shaft being advanceable from a first position outside the patient and into the right ventricle of the heart without penetrating the septum; a second elongate shaft having a proximal end and a distal end; a first elongate flexible body slidably coupled to the first shaft; a second member advanceable from the second elongate shaft; wherein the distal end of the second elongate shaft is configured to be advanced along a second path from a second position outside the heart, through an external wall of the left ventricle and septum, and into the right ventricle; and wherein the second member is configured to be advanced from the second elongate shaft while the distal end of the second elongate shaft is positioned within the right ventricle to enable in situ coupling with the first elongate flexible body so as to join a path of the first elongate shaft and a path of the second elongate shaft; the system further comprising; an implant configured to be advanced along the joined paths, the implant including: a first anchor having a low profile configuration for advancement along the joined paths into the right ventricle and for positioning against the septum; a second anchor for positioning against the external wall of the left ventricle; and an elongate tension member having a first end coupleable with the first anchor and a second end coupleable with the second anchor, the second anchor being slidable along the tension member, the first anchor being configured to deploy laterally from the low-profile configuration within the right ventricle, wherein the tension member is configured to extend from the first anchor in the right ventricle, through the septum and external wall of the left ventricle, and to the second position outside the heart such that tension is applicable between the first anchor and the second anchor with the tension member to urge the septum and the external wall of the left ventricle into engagement and thereby reduce a volume of the left ventricle of the heart. a first elongate shaft having a proximal end and a distal end, the distal end of the first elongate shaft being advanceable from a first position outside the patient and into the right ventricle of the heart without penetrating the septum; a second elongate shaft having a proximal end and a distal end; a first elongate flexible body slidably coupled to the first shaft; a second member advanceable from the second elongate shaft; wherein the distal end of the second elongate shaft is configured to be advanced along a second path from a second position outside the heart, through an external wall of the left ventricle and septum, and into the right ventricle; and wherein the second member is configured to be advanced from the second elongate shaft while the distal end of the second elongate shaft is positioned within the right ventricle to enable in situ coupling with the first elongate flexible body so as to join a path of the first elongate shaft and a path of the second elongate shaft; the system further comprising; an implant configured to be advanced along the joined paths, the implant including: a first anchor having a low profile configuration for advancement along the joined paths into the right ventricle and for positioning against the septum; a second anchor for positioning against the external wall of the left ventricle; and an elongate tension member having a first end coupleable with the first anchor and a second end coupleable with the second anchor, the second anchor being slidable along the tension member, the first anchor being configured to deploy laterally from the low-profile configuration within the right ventricle, wherein the tension member is configured to extend from the first anchor in the right ventricle, through the septum and external wall of the left ventricle, and to the second position outside the heart such that tension is applicable between the first anchor and the second anchor with the tension member to urge the septum and the external wall of the left ventricle into engagement and thereby reduce a volume of the left ventricle of the heart. a first anchor having a low profile configuration for advancement along the joined paths into the right ventricle and for positioning against the septum; a second anchor for positioning against the external wall of the left ventricle; and an elongate tension member having a first end coupleable with the first anchor and a second end coupleable with the second anchor, the second anchor being slidable along the tension member, the first anchor being configured to deploy laterally from the low-profile configuration within the right ventricle, wherein the tension member is configured to extend from the first anchor in the right ventricle, through the septum and external wall of the left ventricle, and to the second position outside the heart such that tension is applicable between the first anchor and the second anchor with the tension member to urge the septum and the external wall of the left ventricle into engagement and thereby reduce a volume of the left ventricle of the heart.