Three Different Morphologies of Inferior Vena Cava Thrombosis: Case Reports

Inferior vena cava (IVC) thrombosis is a rare but significant complication in hospitalized patients. However, relevant information regarding IVC thrombosis, especially on its morphology, remains scarce. We present three cases of IVC thrombosis, with each showing a different morphology: mural, floating, and small polyp-like thrombus. 1. Introduction Deep venous thromboses (DVTs) and pulmonary embolisms (PEs), commonly described together as venous thromboembolisms (VTEs), are important complications in hospitalized patients. DVTs commonly occur in the deep veins of the lower leg or the proximal veins of the iliofemoral segment [1] and rarely occur in the inferior vena cava (IVC) [2–5]. Some case reports and reviews of IVC thrombosis currently exist; however, little information has been published regarding its morphology. We present three cases of IVC thrombosis, with each showing a different morphology. 2. Case Presentations 2.1. Case 1 A 60-year-old man underwent surgical resection for cholangiocarcinoma and was referred to our department because of an IVC thrombus detected on contrast-enhanced abdominal computed tomography (CT), four days later. The patient did not have a family history of VTEs or sudden and/or premature deaths. Prior to his diagnosis, he had not complained of chest pain, dyspnea, or lower back pain. His physical examination showed a regular pulse rate of 96 beats/min, a blood pressure of 106/69？mmHg, and a low-grade temperature of 37.8°C. Auscultation failed to detect any obvious murmur or rales, and peripheral leg edema was not observed. Laboratory tests revealed an increased D-dimer concentration (12.8？μg/mL) and a slightly decreased concentration of antithrombin (55%) and protein C (62%). The patient was also negative for the presence of antinuclear antibody, lupus anticoagulant, and cardiolipin antibody; his protein S concentration was normal. Contrast-enhanced abdominal CT demonstrated the presence of a mural thrombus adhered to the vessel wall in the infrarenal IVC (Figure 1(a)); interruption or hypoplasia of the IVC was not observed. We initially administered anticoagulant therapy with unfractionated heparin and antithrombin to minimize the possibility of bleeding complications. However, the IVC thrombus was found to increase in size, five days later (Figure 1(b)). Thus, we switched to an anticoagulant therapy involving warfarin and fondaparinux sodium, and the IVC thrombosis shrank significantly during the following month of treatment (Figure 1(c)); the patient was then discharged. Figure 1: Contrast-enhanced abdominal computed