The progress of a endovascular cardiac repair can be monitored by inserting a pressure transducer sensor using a catheter into a chamber of the heart during endovascular repair and then using a small, hand-held read out device to measure pressure easily, safely, inexpensively and accurately. In one aspect a sensor is introduced into the body by the steps of folding or rolling the sensor into a cylinder, loading it into a catheter, and deploying into the heart chamber by allowing it to unroll or unfold, either by itself or facilitated by the incorporation of a super-elastic alloy component.