A system for tissue approximation and fixation is described herein. A device is advanced in a minimally invasive manner within a patient's body to create one or several divisions or plications within a hollow body organ. The system comprises a stapler assembly having a tissue acquisition member and a tissue fixation member. The stapler assembly approximates tissue from within the hollow body organ with the acquisition member and then affixes the approximated tissue with the fixation member. In one method, the system can be used as a secondary procedure to reduce the size of a stoma within the hollow body organ.