Cierra, Inc. is developing the PFx™ Closure System, a novel approach for the treatment of Patent Foramen Ovale (PFO). This catheter-based system has for the first time achieved percutaneous PFO closure without leaving behind an implant in the heart. Existing PFO closure methods using implantable devices have offered patients a significant improvement over open-heart surgery, and tens of thousands of PFOs have been closed with implants in the past half-decade. But despite the benefits, the placement of a permanent implant carries the disadvantages associated with a foreign structure remaining in the heart. Cierra’s novel system closes the PFO using “tissue welding” without utilizing an implant. This is done percutaneously using radio frequency (RF) energy that is delivered through Cierra’s proprietary system. The delivery catheter remains entirely within the right atrium, minimizing risks associated with devices in the left atrium. Cierra is the seventh portfolio company from the medical device incubator, The Foundry, and is privately held. Its venture investors are Split Rock Partners, Morgenthaler Ventures, Frazier Healthcare Ventures and Delphi Ventures.