A repair structure apparatus for cardiac surgery is disclosed. The repair structure apparatus includes a fluid reservoir and a platform comprising a porous surface in communication with the fluid reservoir, with a port in communication with the porous surface. The apparatus includes a cutting template configured to align with the platform and a slicing sled configured to engage the platform. A cutting template for constructing a repair structure for cardiac surgery is further disclosed. The cutting template includes a frame having at least one arcuate lobe; and at least one sharpened edge. A device for constructing a repair structure for cardiac surgery is also disclosed, wherein the device includes a porous platform. A repair structure for cardiac surgery is disclosed. The repair structure includes a tissue sheet, wherein the tissue sheet is folded along a free edge of the tissue sheet.