A graft device is provided comprising a flow conduit and a surrounding covering. The graft device is for connecting between a first body space and a second body space. In one embodiment, the flow conduit is a vein, such as a harvested saphenous vein, useful as an arterial graft, for example and without limitation, in a coronary artery bypass procedure. Also provided are methods of preparing a graft device and connecting the graft between a first body space and a second body space, such as the aorta and a location on an occluded coronary artery, distal to the occlusion.