An apparatus and method for closing an opening in a blood vessel wall is disclosed. The apparatus includes at least one member which is extended through a tissue tract formed through the epidermis and subcutaneous layer of skin and through the opening in the blood vessel. The member includes a proximal end and a distal end with the distal end being positionable proximate to the opening in the blood vessel wall. A positive electrode is positioned next to the distal end with a negative electrode being positioned next to the proximal end When the electrodes are energized an electric field is created therebetween, blood cells are attracted to the positive electrode, and a thrombus is formed at the opening in the blood vessel wall. The member may include a balloon at the distal end to temporarily occlude blood flow from the blood vessel to the tissue tract to facilitate formation of the thrombus. In addition, the shape of the balloon may be tailored to facilitate the formation of the thrombus including, but not limited to, the creation of pockets and self-supporting balloons.