Intracardiac Thrombus in Transit and Risk of Paradoxical Embolism

Abstract

INTRODUCTION: A thrombus in transit is a rare complication that occurs when a deep venous thrombus migrates from the right to the left side of the heart through an interatrial defect. An intracardiac thrombus in transit poses the risk of paradoxical embolism, cardioembolic stroke and high mortality. We present a case of a patient found to have a large intracardiac thrombus in transit managed with systemic anticoagulation and surgical embolectomy with a good outcome. CASE PRESENTATION: A 30-year-old male presented with one week of chest pain, dyspnea on exertion and chills. His vitals were HR 108 bpm, BP 136/87, T 36.4 C, RR 27, saturating 97% on 3 liters nasal canula. A loud S2 on cardiac auscultation was heard but the rest of his physical exam was unremarkable. EKG showed sinus tachycardia with T wave inversions in V2 to V4. Chest X-ray demonstrated normal cardiac silhouette and was unremarkable for pulmonary pathology. CT pulmonary angiography showed a linear saddle embolus extending across the branch point of the right and left main pulmonary arteries (PA) with filling defects of the right PA to the upper, middle, and lower lobe branches and the left PA to the proximal left upper lobe and left lower lobe branches. The RV/LV diameter ratio was >0.9 suggestive of RV strain and the main PA was dilated. Echocardiogram showed a large thrombus in the RA that extended through either a PFO or a secundum ASD into the LA. The RV was dilated with systolic flattening of the interventricular septum with an estimated RVSP of 52 mm Hg. He was started on intravenous heparin and cardiothoracic surgery was consulted for submassive PE with coexisting thrombus-in-transit. The patient underwent a pulmonary embolectomy with successful removal of the intracardiac thrombus and repair of the ASD. He was discharged home without complications on warfarin.