An assembly for effecting the condition of a mitral valve of a heart includes a mitral valve therapy device, a guide wire, and a guide tube. The mitral valve therapy device is configured to reshape the mitral valve annulus of the heart when placed within the coronary sinus adjacent the mitral valve annulus. The guide wire is configured to be fed into the coronary sinus of the heart adjacent the mitral valve annulus. The guide tube has a distal end, a proximal end, and a lumen extending between the distal end and the proximal end. The guide tube further includes a side port, intermediate the distal and proximal ends which communicates with the lumen. This permits the guide tube to be slidingly received on the guide wire with the guide wire extending from the distal end, through the lumen, and out the side port. In use, the guide tube is slid along the guide wire into the coronary sinus. The mitral valve therapy device is then delivered by the guide tube into the coronary sinus adjacent the mitral valve annulus.