Valve ring contraction device

The invention discloses a valve ring contraction device which comprises a valve ring positioning mechanism and an anchoring ring contraction mechanism, the valve ring positioning mechanism comprises a support body, a developing connecting pipe and a developing fixing pipe, and the support body is formed by bending and heat-setting a memory alloy wire and comprises a leftward supporting wing, a right supporting wing and a plurality of positioning supporting feet extending downwards. The stent body can be contracted before an operation and installed in a catheter and can be automatically expanded and expanded in the heart after being released from the catheter during the operation, the left branch wing and the right branch wing are attached to and abut against the atrial wall in a self-adaptive mode after the stent body is expanded, and the positioning supporting foot is inserted and positioned at the junction of two valve leaflets of a valve ring. The ends, close to each other, of the left supporting wing and