Abstract: A prosthetic valve delivery assembly includes a dilator including a first tapered region extending along a dilator axis. The first tapered region includes a tapered shape with a first diameter at a distal end and a second diameter at a first central end. The second diameter is greater than the first diameter. A central region includes the second diameter that is substantially constant along a central length of the central region. A second tapered region includes a tapered shape with the second diameter at the second central end and a third diameter at a third central end. The third diameter is less than the second diameter. A proximal shaft region extends from the third central end. The proximal shaft region includes the third diameter such that a difference between the second diameter and the third diameter is within a French gauge range from about 3 Fr to about 5 Fr.