1. A computer-implemented method for enabling the assessment of a coronary artery of a patient, based on a calculated fractional flow reserve value, the method comprising: displaying, on a digital display device, a three-dimensional model of at least a portion of multiple coronary arteries branching from an aorta of the patient, wherein the three-dimensional model is provided by a computer system; displaying, on the display device, a first fractional flow reserve calculated by the computer system for at least one of the coronary arteries in the three-dimensional model; receiving an input to the computer system related to a treatment plan for the at least one of the coronary arteries, wherein the treatment plan includes a widening of a lumen defined by the at least one of the coronary arteries; and calculating and displaying, on the display device, a second fractional flow reserve for the at least one of the coronary arteries, wherein calculation of the second fractional flow reserve is based at least in part on the received input.