A paired, expandable anastomosis device joins two vessels together and can expand and contract with changes in the size of the two vessels. The anastomosis device has two expandable rings with a plurality of holding tabs. The holding tabs of one ring are shaped to enable a graft vessel tissue to be everted through one of the rings and to be held on one of the rings. Similarly, the holding tabs of the other ring are shaped to enable a target vessel to be everted through the other ring and to be retained by the holding tabs. Once the graft and target vessels are loaded, the rings are adapted to be brought together to a position in which the graft and target vessels are anastomosed together.