Methods and devices for transvascular prosthetic chordae tendineae implantation are disclosed. A catheter is advanced into the left atrium. From an atrium side, a leaflet anchor having a leaflet suture is secured to the mitral valve leaflet. A ventricular anchor is anchored to the wall of the ventricle to secure the ventricular wall to a ventricle suture. The leaflet suture and the ventricle suture may be tensioned and connected by a suture lock to form an artificial chordae. The suture lock has a body with a suture path extending therethrough. A wall in the housing is movable to reduce the cross section of the suture path. A drive mechanism advances the movable wall to clamp sutures extending through the suture path, in response to rotation of a coupling on the housing.