Embodiments of the present disclosure are configured to assess the severity of a blockage in a vessel and, in particular, a stenosis in a blood vessel. In some particular embodiments, the devices, systems, and methods of the present disclosure are configured to assess the severity of a stenosis in the coronary arteries without the administration of a hyperemic agent. Further, in some implementations devices, systems, and methods of the present disclosure are configured to normalize and/or temporally align pressure measurements from two different pressure sensing instruments. Further still, in some instances devices, systems, and methods of the present disclosure are configured to exclude outlier cardiac cycles from calculations utilized to evaluate a vessel, including providing visual indication to a user that the cardiac cycles have been excluded.
