A system for evaluating cardiovascular treatment options for a patient, the system comprising: at least one computer system configured to: create a three-dimensional model representing at least a portion of the patient's heart or vasculature based on patient-specific data regarding a geometry of the patient's heart or vasculature; for each of a plurality of treatment options, modify at least one of the three-dimensional model or a reduced order model of the patient's heart or vasculature based on a respective one of the treatment options; determine, for each of the plurality of treatment options, a value of a blood flow characteristic calculated from at least one of the modified three-dimensional model and the modified reduced order model; and identify, among said plurality of treatment options, one or more treatment options that optimizes an objective cost function calculated based on at least one of the blood flow characteristics of the patient's heart or vasculature, and based on penalties applied to treatment options by the objective cost function, characterised by said objective cost function being configured to penalize one or more of: decreasing of FFR values in larger vessels, as opposed to smaller vessels; increasing proximity of inserted stents; and the existence or number of bifurcations. at least one computer system configured to: create a three-dimensional model representing at least a portion of the patient's heart or vasculature based on patient-specific data regarding a geometry of the patient's heart or vasculature; for each of a plurality of treatment options, modify at least one of the three-dimensional model or a reduced order model of the patient's heart or vasculature based on a respective one of the treatment options; determine, for each of the plurality of treatment options, a value of a blood flow characteristic calculated from at least one of the modified three-dimensional model and the modified reduced order model; and identify, among said plurality of treatment options, one or more treatment options that optimizes an objective cost function calculated based on at least one of the blood flow characteristics of the patient's heart or vasculature, and based on penalties applied to treatment options by the objective cost function, create a three-dimensional model representing at least a portion of the patient's heart or vasculature based on patient-specific data regarding a geometry of the patient's heart or vasculature; for each of a plurality of treatment options, modify at least one of the three-dimensional model or a reduced order model of the patient's heart or vasculature based on a respective one of the treatment options; determine, for each of the plurality of treatment options, a value of a blood flow characteristic calculated from at least one of the modified three-dimensional model and the modified reduced order model; and identify, among said plurality of treatment options, one or more treatment options that optimizes an objective cost function calculated based on at least one of the blood flow characteristics of the patient's heart or vasculature, and based on penalties applied to treatment options by the objective cost function, characterised by said objective cost function being configured to penalize one or more of: decreasing of FFR values in larger vessels, as opposed to smaller vessels; increasing proximity of inserted stents; and the existence or number of bifurcations.