Abstract

May–Thurner syndrome (MTS, also known as iliac vein compression syndrome) is a vascular disorder characterized by pelvic venous compression that may lead to chronic venous insufficiency or deep vein thrombosis. Optimal management requires accurate diagnosis and identification of functionally significant venous stenosis. Conventional imaging modalities, such as magnetic resonance venography (MRV) and computed tomography venography (CTV), primarily delineate anatomical obstruction but provide limited information on hemodynamic relevance. Fractional flow reserve (FFR), originally developed for coronary artery disease as a physiological index based on distal-to-proximal pressure gradients, has been proposed in preliminary studies as a potential adjunct for venous assessment. This narrative review examines the potential role of FFR in this context, drawing on evidence from arterial applications and initial venous explorations. Available data suggest that FFR enables quantitative assessment of pressure gradients across stenotic segments, but its applicability in the venous system remains theoretical due to fundamental differences in venous flow physiology. Incorporating FFR into diagnostic pathways could hypothetically improve patient selection for venous stenting, reduce unnecessary interventions, and enhance symptom management. However, concerns regarding technical feasibility, lack of standardized cut-off values, and potential for misdiagnosis must be addressed. Well-designed prospective studies are required to establish whether FFR can be reliably translated into routine venous diagnostics.

Key words: May–Thurner syndrome, venous insufficiency, fractional flow reserve, intravascular ultrasound, hemodynamics, vascular diagnostics