A Severe COVID-19 Case Complicated by Right Atrium Thrombus.

BACKGROUND Recent studies demonstrated evidence of coagulation dysfunction in hospitalized patients with severe coronavirus disease 2019 (COVID-19) due to excessive inflammation, hypoxia, platelet activation, endothelial dysfunction, and stasis. Effective anticoagulation therapy may play a dominant role in the management of severe COVID-19 cases. CASE REPORT A 73-year-old man with a 6-day history of fever up to 38.5°C, dyspnea, cough, and fatigue was diagnosed with COVID-19. He had a past medical history significant for hypertension and coronary artery bypass grafting. Two days after hospital admission, the patient developed acute respiratory failure, requiring intubation, mechanical ventilation, and transfer to the intensive care unit (ICU). He received treatment including antibiotics, hydroxychloroquine, tocilizumab, vasopressors, prone positioning, and anticoagulation with enoxaparin at a prophylactic dose. After a 15-day ICU stay, the patient was hemodynamically stable but still hypoxemic; a transthoracic echocardiogram at that time, followed by a transesophageal echocardiogram for better evaluation, revealed the presence of a right atrium thrombus without signs of acute right ventricular dilatation and impaired systolic function. Since the patient was hemodynamically stable, we decided to treat him with conventional anticoagulation under close monitoring for signs of hemodynamic deterioration; thus, the prophylactic dose of enoxaparin was replaced by therapeutic dosing, which was a key component of the patient's successful outcome. Over the next few days he showed significant clinical improvement. The follow-up transesophageal echocardiogram 3 weeks after effective therapeutic anticoagulation revealed no signs of right heart thrombus. CONCLUSIONS The presented COVID-19 case, one of the first reported cases with evidence of right heart thrombus by transesophageal echocardiography, highlights the central role of diagnostic imaging strategies and the importance of adequate anticoagulation therapy in the management of severe COVID-19 cases in the ICU.