A low profile transseptal catheter and implant system is disclosed. Access to the mitral valve can be obtained using femoral catheterization with a fluoroscopically guided, low-profile catheter. For example, the right atrium is accessed and the interatrial septum punctured to access the left atrium, and the mitral valve is approached through the left atrium. Advantageously, this approach avoids contact with the left ventricular outflow tract and the chordae tendinae. Two leaflet braces are extended over guide wires to form semicircular loops that circumnavigate the anterior and posterior mitral valve leaflets. Tension is applied to the catheter from the atrial direction to keep the leaflet braces tightly wedged under the leaflets for the remainder of the procedure. A fastener joins the ends of each loop to create one annular ring encircling the valve under the anterior and posterior leaflets.