John Simpson has helped revolutionize the field of medicine through innovations that fundamentally altered how physicians treat cardiovascular disease. In 1981 he created a new catheter system for coronary angioplasty with an independently steerable guidewire in the central lumen of the balloon catheter, patented as the over-the-wire balloon angioplasty catheter. This contribution was essential in enabling selective catheterization of distal vessels and allowing treatment of previously inaccessible stenoses in tortuous vessels while preventing inappropriate entry into collateral branches. 

He founded Avinger, Inc. in 2007 and served as its CEO and then executive chair before retiring in December 2017. He also started numerous other companies, including Advanced Cardiovascular Systems, Perclose, FoxHollow Technologies, and Devices for Vascular Intervention. He now focuses his efforts on the treatment of vascular disease through the development of new technologies combined with a new approach to optical imaging.

He is a member of the American College of Physicians and fellow in the American College of Cardiology, and has published on a variety of medical subjects and lectured extensively throughout the world.

Dr. Simpson received his MS and PhD in biomedical sciences from the University of Texas and his MD from Duke University, and completed his fellowship in interventional cardiology at Stanford University.