Devices, systems, and methods for assessing a vessel

A system for evaluating a stenosis of a vessel of a patient, the system comprising:

• a processing unit configured for communication with a pressure-sensing guide wire and a pressure-sensing instrument, wherein the processing unit is configured to:
• receive proximal pressure measurements for a plurality of cardiac cycles of the patient from the pressure-sensing instrument;
• receive distal pressure measurements for the plurality of cardiac cycles from the pressure-sensing guide wire, wherein the proximal pressure measurements and the distal pressure measurements are obtained without application of a hyperemic agent to the patient;
• perform a pressure ratio calculation based on the proximal pressure measurements and the distal pressure measurements, wherein the pressure ratio calculation results in a plurality of pressure ratios corresponding to the plurality of cardiac cycles;
• monitor the pressure ratio calculation to detect an anomaly impacting a cardiac cycle of the plurality of cardiac cycles;
• automatically exclude a pressure ratio of the plurality of pressure ratios corresponding to the impacted cardiac cycle;
• and
• output, to a display in communication with the processing unit, a pressure ratio indicator based on the plurality of pressure ratios other than the excluded pressure ratio.