Bilateral deep vein thrombosis (DVT) should prompt investigation for pro-thrombotic conditions and the exclusion of vascular compromise due to intrinsic and extrinsic factors. The authors present the case of a 47-year-old man admitted with bilateral DVT and diagnosed with inferior vena cava (IVC) infra-renal segment agenesis, and discuss the management of this rare condition. LEARNING POINTS • Bilateral deep vein thrombosis in young and otherwise healthy individuals should prompt investigation of the aetiology and risk factors in case lifelong treatment and anticoagulation therapy is required. • Although rare, anatomical variations and congenital malformations should be considered even in adult patients. • Rare medical cases should prompt a multidisciplinary approach to investigation and treatment, as prognosis will depend on both therapeutic procedures and anticipation of complications. KEYWORDS Deep venous thrombosis, absence of inferior vena cava, inferior vena cava anomalies