Transcatheter valve prosthesis

A method for implanting a replacement valve in a patient's heart, comprising:

• advancing an elongate outer member from a first delivery catheter to form a loop around native valve leaflets and/or chords of a native valve with the elongate outer member without substantially occluding the native valve;
• partially deploying from a second delivery catheter a radially self-expandable tubular body having an inflow end and an outflow end, a valve disposed within a lumen of the tubular body, and a preformed groove disposed at an outer surface of the tubular body between the inflow end and the outflow end, the preformed groove extending at least partially around the tubular body and having a circumferential opening facing radially outward of the tubular body, such that, when the tubular body is partially deployed, the native valve is substantially occluded;
• moving the loop into the preformed groove after partially deploying the tubular body from the second delivery catheter;
• and
• fully deploying the tubular body from the second delivery catheter after moving the loop into the preformed groove so that the native valve is no longer substantially occluded.