TY - JOUR AU - Kirsten van Langevelde, AU - Alexandr Šrámek, AU - Patrice W.J. Vincken, AU - Jan-Kees van Rooden, AU - Frits R. Rosendaal, AU - Suzanne C. Cannegieter, PY - 2013/02/01 Y2 - 2024/03/19 TI - Finding the origin of pulmonary emboli with a total-body magnetic resonance direct thrombus imaging technique JF - Haematologica JA - haematol VL - 98 IS - 2 SE - Articles DO - 10.3324/haematol.2012.069195 UR - https://haematologica.org/article/view/6570 SP - 309-315 AB - Pulmonary embolism is considered to originate from embolization of a deep-vein thrombosis, resulting in two manifestations of one disease: venous thrombosis. However, in up to 50% of patients with pulmonary embolism no deep-vein thrombosis is found with ultrasonography. An explanation for this low proportion is currently lacking. Other imaging modalities may increase the yield of detection of deep-vein thrombosis in the calf or in the abdominal region. Alternatively, not all pulmonary emboli may originate from deep-vein thromboses in the extremities. We searched for the origin of pulmonary emboli, by performing total-body magnetic resonance imaging-scans to visualize thrombi. Ninety-nine patients with a first pulmonary embolism confirmed by computed tomography underwent a magnetic resonance direct thrombus imaging-scan, a validated technique using endogenous contrast. Additionally, acquired and genetic risk factors were assessed. No thrombus was found in 55 patients, whereas a thrombus was identified in 44 patients. The commonest thrombus location was the lower leg; 12 patients had isolated calf vein thrombosis and five had isolated superficial vein thrombosis. A peripheral thrombus was found by magnetic resonance imaging in less than half of patients with pulmonary embolism. We propose several hypotheses to explain the absence of thrombi, such as a cardiac thrombus origin or embolization of the whole deep-vein thrombus. The possibility that pulmonary embolism arises de novo in the lungs, due to local inflammation-driven coagulation, needs to be considered. ER -