OPTICA study (NCT 04179487) overview, outlining inclusion and exclusion criteria, CTPA protocol parameters, and settings.Inset: The scan range for the OPTICA study extends from below the humeral heads to approximately 2  cm below the lowest dome of diaphragm. C/I, contraindication; CrCl, creatinine clearance (calculated by Cockroft-Gault equation); CT, computed tomography; PE, pulmonary embolism; UFH, unfractionated heparin; US, ultrasound; VKA, vitamin K antagonist.