Access closure configuration

A method for forming an expandable tract across a wall of a blood vessel, comprising:

• a. creating a first passage across the wall with a sharpened member at a first angle relative to a lumen longitudinal axis defined by a lumen of the blood vessel in the region adjacent the first passage;
• b. advancing an anchor assembly through the first passage such that a distal portion of the anchor assembly is placed within the lumen of the blood vessel;
• c. applying a force to the anchor assembly to position an adjacent portion of the blood vessel wall into a desired contact configuration relative to the anchor assembly;
• d. while maintaining the desired contact configuration, advancing a needle through a portion of the anchor assembly and through a portion of the wall of the blood vessel to form an expandable tract between overlapping tissue portions of the vessel wall,
• wherein a portion of the anchor assembly comprises a saddle-shaped needle receiving structure configured to receive and support the needle after it has been advanced across the portion of the wall to create the expandable tract.