The present invention is directed to various systems for repairing tissue within the heart of a patient. The mitral valve repair system of the present invention comprises a guide catheter having a proximal end, a distal end, and at least one internal lumen formed therein, a therapy catheter capable of applying a suture to the tissue, and a fastener catheter capable of attaching a fastener to the suture. The therapy catheter and the fastener catheter are capable of traversing the internal lumen of the guide catheter. In addition, the present invention discloses various methods for repairing tissue within the heart of a patient. In one embodiment, the method of repairing heart valve tissue includes advancing a guide catheter through a circulatory pathway to a location in the heart proximate to a heart valve, advancing a therapy catheter through the guide catheter to the heart valve, stabilizing a first leaflet with the therapy catheter, deploying a first suture into the stabilized first leaflet, disengaging the first leaflet from the therapy catheter while leaving the first suture attached thereto, stabilizing a second leaflet with the therapy catheter, deploying a second suture into the second leaflet, disengaging the second leaflet from the therapy catheter while leaving the second suture attached thereto, and joining the first and second leaflets by reducing the distance between the first and second sutures.
