Pressure based blood vessel assessment systems and methods

A system for assessing a vascular condition, comprising:

• a pressure sensing catheter configured to be positioned at a proximal position within vasculature of a patient;
• a pressure guidewire configured to be positioned at a distal position within the vasculature, the distal position being located distal to the proximal position;
• and
• one or more hardware processors configured to:
• detect heartbeats of the patient while the pressure sensing catheter and the pressure guidewire are positioned at the proximal and the distal positions in the vasculature respectively;
• locate a diastolic pressure ratio (dPR) zone within a heartbeat from analysis of a signal from at least one of the pressure sensing catheter and the pressure guidewire;
• calculate a dPR value including calculating an average of a plurality of ratios of proximal pressure (Pa) to distal pressure (Pd) taken over time within the dPR zone;
• calculate a multi-beat metric including the dPR value and a whole heartbeat pressure ratio;
• and
• output the multi-beat metric.