Which procedure are you refering to? there does seem to be a 'minial invasive' label attached to a few procedures. I know that two years ago, aortic valves were replaced successfully in patients in Kings College in London using just a catheter through the artery in the leg, just like an angiogram. The collapsed valve replacement was sent to the correct position and expanded into place using a balloon, squashing the old valve leafs into the heart. As soon as the balloon was deflated, the valve started working immediately. I dont know if this has become common practice now though.
Here is a link showing that procedure.