The hype surrounding renal denervation (RDN) came crashing down in early 2014 after the failed SYMPLICITY HTN-3 trial sidelined front-runner Medtronic plc and spooked several of its smaller challengers, at least where the U.S. market was concerned. Then, last year, Dublin-based Medtronic revived hope for the RDN field by re-launching a revised version of its clinical program for the technology.