A Marantic Endocarditis Complicating a Metastatic Gastric Adenocarcinoma Initially Resistant to Low-molecular Weight Heparin: A Case Report

Abstract

Background: Marantic endocarditis is a rare paraneoplastic syndrome which results from an hypercoagulate state. It can be associated with several tumors, particularly gastric cancer, and histology of adenocarcinoma. Mucines secreted by adenocarcinoma contribute to the activation of the coagulation pathway. Case presentation: We present the case of a patient with a marantic endocarditis complicating a metastatic gastric adenocarcinoma. He was hospitalised for a thoracic pain. At the physical examination, we found swelling, redness, and warmth of the right lower limb, suspected for a deep vein thrombosis that was confirmed at the echo doppler ultrasound. CT scan documented a severe bilateral pulmonary embolism, a splenic infarction, and multiple liver metastases. Laboratory tests were normal. Despite a Low-Molecular Weight Heparin (LMWH) treatment, the patient presented a cerebral stroke, confirmed at the MRI. Trans-thoracic echocardiography found a small vegetation of the mobile end of the mitral valve with a normal left ventricular contractile function. LMWH was switched by continuous intravenous Unfractionated Heparin (UFH). PET scan showed multiple liver metastases and a pathological gastric hypermetabolism. Liver biopsy confirmed a metastasis of a HER-2 negative gastric adenocarcinoma. Because of the stop of heparin treatment during this procedure, the patient presented a new brain stroke. A systemic palliative chemotherapy was started by FOLFOX-4 regimen and it is now ongoing. Conclusion: The particularity of this case relies on the impossibility to initially switch UFH by another anticoagulant treatment. Chemotherapy represents the only possibility to decrease mucine production and thrombi formation.