A CLOG IN THE RV: RIGHT VENTRICULAR THROMBUS IN TRANSIT

Abstract

TOPIC: Pulmonary Vascular Disease TYPE: Medical Student/Resident Case Reports INTRODUCTION: Right ventricular (RV) thrombi are an uncommon condition associated with pulmonary embolism. They may form within the cardiac chamber due to structural heart disease or presence of foriegn objects such as a ventricular assist device, or may represent a thrombus in transit from a peripheral source. We present the case and imaging of a patient who presented with extensive thrombosis involving the right ventricle and pulmonary arteries, in the context of periprocedural interruption of anticoagulant therapy. CASE PRESENTATION: A 35-year-old woman with a history of hypothyroidism, polycystic ovaries, and recently diagnosed metastatic cholangiocarcinoma presented with sudden onset right sided sharp chest pain and shortness of breath, in association with left calf pain. She had been on rivaroxaban for a history of venous thromboembolism, which had been interrupted peri-procedurally for implantation of a port. Physical examination was notable for hypoxia (oxygen saturation 85% on room air), hypotension (96/48 mm Hg), tachypnea, and signs of respiratory distress. Laboratory workup showed elevated N-terminal proBNP (748 pg/mL), with normal troponin. Computed tomography (CT) imaging of the chest with contrast demonstrated a large right ventricular thrombus extended through the pulmonic valve into the main pulmonary artery and its bifurcations, with numerous bilateral lobar, segmental and subsegmental emboli. Systemic anticoagulation with heparin was initiated. She was deemed not to be a candidate for catheter based thrombolysis, owing to the position of the thrombus, and neither for open cardiac surgery, given the late stage of her malignancy. She was started on a morphine infusion for relief of pain, and was transitioned to hospice shortly thereafter. DISCUSSION: In one study RV thrombus was found to be present in about 4% of cases of pulmonary embolism.[1] RV thrombi can be classified into various groups, depending on the shape and mobility of the thrombus.[2] We present this case to demonstrate the imaging findings of extensive RV thrombosis contiguous with thrombosis in the main pulmonary artery. There are no guidelines and little evidence on the best approach to the treatment of RV thrombi. While thrombolysis is indicated in patients with a massive pulmonary embolism, its utility in patients with RV thrombosis without hemodynamic instability remains less clear. Catheter based thrombolysis can be challenging, as in our patient, if the anatomy of the thrombus is such that it precludes adequate placement of the catheter. CONCLUSIONS: The diagnosis and management of RV thrombus is challenging; further studies and guidelines are warranted. REFERENCE #1: Casazza F, Becattini C, Guglielmelli E, et al. Prognostic significance of free-floating right heart thromboemboli in acute pulmonary embolism: results from the Italian Pulmonary Embolism Registry. Thromb Haemost. 2014 Jan;111(1):53-7. REFERENCE #2: Naeem K. Floating thrombus in the right heart associated with pulmonary embolism: The role of echocardiography. Pak J Med Sci. 2015 Jan-Feb; 31(1): 233–235. DISCLOSURES: No relevant relationships by Dan Kazmierski, source=Web Response No relevant relationships by Si Li, source=Web Response No relevant relationships by jacob miller, source=Web Response No relevant relationships by Pius Ochieng, source=Web Response No relevant relationships by Dhaval Patel, source=Web Response No relevant relationships by NISHANT SHARMA, source=Web Response