A guidewire has a guidewire body with a distal end and a proximal end. A balloon or other tissue anchor is disposed at or near the distal end of the guidewire, and the guidewire may be used to draw two layers of tissue into apposition by placing the guidewire through a tissue penetration, deploying the tissue anchor, and drawing proximally on the guidewire body. Optionally, the guidewire may include deployable blades for enlarging a tissue penetration as the guidewire is advanced therethrough.