A British six-year-old boy has become the first person in the world to have a heart valve widened using an MRI scan for guidance rather than X-ray imaging. <br/><br/>Jack Walborn was born with the heart condition pulmonary valve stenosis, which reduces blood flow to the lungs. Using MRI means patients are not exposed to radiation – particularly important for children. The scan also provides a clearer image, and information about the body's tissues, in real time during surgery. <br/><br/>Jack's condition meant that the flow of blood from the right side of his heart was obstructed. Surgeons decided he needed an operation called a valvuloplasty to widen the valve and increase blood flow. This is done by inserting a catheter into a blood vessel in the arm or groin and guiding it to the heart.<br/><br/>At the tip of the catheter is a balloon which is gently inflated to widen the narrowed valve. X-ray imaging is usually used to track the progress of the catheter through the body. But a team at the King's Health Partners Academic Health Sciences Centre in London has developed a way to use MRI scanning instead.