FIGURE 1. The MitraXs (St Jude Medical Inc, Minneapolis, Minn) is a self-supporting atrial retractor. A, In deployed position with 1 overmoduled pivoting rivet that makes its conical shape self-expanding and auto-adjusting. B, In rolled and compressed position, with triangular tab protruding out of the cylinder, which makes introduction into the left atrium easy. CLINICAL SUMMARY The MitraXs retractor is a pattern-cut polymer sheet that once deployed and secured by a pivoting rivet generates a conical volume (Figure 1). The device is a self-expanding, auto-adjusting, single-use left atrial retractor that does not require a supporting arm. The retractor has 2 sizes (A and B) according to valve diameter and 2 lengths (regular or ‘‘ þ’’) according to atrium depth to accommodate anatomic variations. The introduction and deployment of the MitraXs device are key points. After the folding step, the MitraXs device is rolled and compressed from a conical shape to a cylinder with a reduced diameter creating a protruding triangular tab (Figure 1). By using a locking forceps, theMitraXs device is introduced via a minithoracotomy and an atriotomy, the tab with the rivet at the top loading the atrial septum first; then, with a clockwise rotation of a half turn, the device is progressively pushed into the left atrium in a screwing movement. When the MitraXs device is completely engaged in the left atrium, centered on the valve, with the rivet down in the posterior position, the forceps is released and the retractor deploys back into an optimal conical shape, working as an ‘‘expander’’ and maintaining the left atriumwide open in a symmetric manner. The effectiveness of the MitraXs device was evaluated in 62 patients who consecutively underwent MIMVS during a 20-month period at the Louis Pradel Hospital. There