A percutaneously implantable device for the treatment of a cardiac condition or other disease is disclosed herein, the device capable of delivery and maintenance of a therapeutic scaffold. A therapeutic scaffold may comprise viable tissue to impart or restore normal cardiac function, or other therapeutic agent for the treatment of disease or injury. Viable tissue may comprise a pacemaker gene or other genes intended to impart a pacemaker function to either host tissue or transplanted tissue, or both. Further, a device according to the invention may be used for the implantation and maintenance of viable tissue to induce or enhance muscle contraction of a subject for the treatment of a disease or disorder.