Intravascular cardiac restraining implants designed for treatment of heart disease and heart failure and methods for their use. The disclosed implants can be used to reshape or reinforce a diseased, weakened or distended portion of a patients heart to counteract heart disease and heart damage. An intravascular cardiac restraining implant may include a first tissue anchor configured for implantation in a first region of a coronary vein, a second tissue anchor configured for implantation in a second region of the coronary vein, and at least one elongate member coupled to the first tissue anchor and the second tissue anchor. In one embodiment, the at least one elongate member may be a spring or a similar device configured for biasing the first and second tissue anchors toward one another, thus reshaping or reinforcing a diseased, weakened or distended portion of a patients heart.