Evaluating the success of transcatheter aortic valve implantation

18F-fluoride in the identification of bioprosthetic valve degeneration following surgical and transcatheter implantation

Every year in the UK, thousands of people undergo life-saving surgery to replace a diseased aortic valve. The aortic valve sits at the exit of the heart, allowing fresh blood to flow to the rest of the body while stopping it leaking back into the heart. Until recently, doctors replaced a diseased aortic valve by opening up the chest. However, now in some patients, doctors can replace the valve using a less invasive procedure, delivering the replacement valve to the heart through an artery using a catheter. For this procedure (called transcatheter aortic valve implantation, or TAVI) they need only make a small cut in the groin or below the collarbone. As the introduction of TAVI is relatively recent, we don't know how long these replacement valves will last compared with traditional aortic valve replacement. There is a risk with any valve replacement that calcium builds up inside the valve tissue, causing it to stiffen. With time the valve may no longer open and close properly and patients may need another operation. Dr Marc Dweck’s team, from the University of Edinburgh, will use sophisticated imaging techniques (CT and PET scans) to visualise replacement valves in 180 patients. They will look for any signs of calcium build-up or degeneration that may be starting to affect valve function. This will give researchers a better idea of how long these newer valves last, and will also benefit individual patients directly through better monitoring after the procedure.