A sudden death case after repeated pulmonary embolization of venous thrombi formed by the compression of the inferior vena cava by a horseshoe kidney

We present the unexpected death of an elderly man who died from saddle thromboemboli in the pulmonary artery trunk and organized thrombi in the distal arteries in every lobe. The inferior vena cava was compressed between the horseshoe kidney and ossified spinal ligament, thereby generating fresh thrombi (aged within three days) composed of numerous erythrocytes, platelets, neutrophils, and fibrin fibers. Cardiac hypertrophy with a myocardial lesion reduces the cardiac reserve. The lobar and segmental arteries contained not only fresh emboli but also mural and luminal thrombi at various stages of organization. Organized thrombi with recanalized neo-vessels were further connected with collateral bronchial artery circulation. These remodeling reactions maintained pulmonary blood flow until the last embolization. A year prior to his death, the patient became aware of his illness. Four months before death, he was hospitalized and pulmonary emboli were found, but neither their cause nor origin was detected. The clinical course, histological, and computed tomography findings imply that repeated inferior vena cava compression generated thrombi, resulting in pulmonary embolization and remodeling.