A percutaneously implantable chamber for the treatment of a cardiac condition is disclosed herein, the chamber capable of delivery and maintenance of viable cells comprising a pacemaker gene or other genes intended to impart a specific function via a host cell. An artificial sinoatrial node and artificial atrial ventricular node for the restoration of the pacemaker function of the heart of a subject comprises a chamber comprising cells expressing a pacemaker gene. Further, a chamber may be used for the implantation and maintenance of viable, responsive, immunoisolated cells to induce or enhance muscle contraction of a subject for the treatment of a disorder.