A Tkatchev is a difficult release move named after Soviet gymnast Alexander Tkatchev. It's also called a reverse hecht.
A Tkatchev is performed on the high bar or uneven bars, and can be done in the straddle, pike, or layout position.
In a Tkatchev, the gymnast swings up like a back giant and releases the bar in an arched position. She flies over it with her back to it, then sits up and catches the bar again.