Right Heart Thrombus with High-Risk Pulmonary Embolism in COVID-19 Pneumonia, a POCUS Diagnosis

Case Presentation: A 74-year-old female nursing home patient with a history of ischemic stroke, hypertension, and obesity presented with fever, dyspnea, and hypoxemia to the emergency department. A chest radiograph demonstrated diffuse bilateral infiltrates and a rapid COVID-19 PCR was positive. She was emergently intubated and developed hemodynamic instability requiring multiple vasopressors, and her extremities were noted to be cool and clammy. Point-of-care ultrasound (POCUS) revealed a large irregularly shaped mobile hyperechoic density transiting the tricuspid valve as well as a dilated right ventricle. She was started on unfractionated heparin for concern of acute pulmonary embolism, though she did not undergo diagnostic imaging due to her hemodynamic instability and COVID-19 status. Bedside findings were formally confirmed by an emergent formal transthoracic echocardiogram and intravenous alteplase was administered. Her hemodynamics stabilized shortly after and she was weaned from vasopressor support. A repeat POCUS the following day showed resolution of the thrombus. Discussion: COVID-19 has altered the risk-benefit calculus of many clinical activities, impacting the availability of imaging due infection control, transport, and staffing issues. POCUS can serve as an efficient diagnostic modality in times of limited resources and/or emergent situations requiring rapid bedside diagnosis. Management of a moderate-to-high risk pulmonary embolism (PE) with anticoagulation is a widely accepted practice, and thrombolytics should be considered when hemodynamic instability is present. However, the management is less clear when a right heart thrombus (RHT) is found. The incidence of RHT ranges from 4-18%, though its identification is expected to increase with the rising popularity and training of POCUS. A RHT is considered a medical emergency given the high propensity of progression to a PE and increased mortality rate. Treatment with thrombolytics in addition to anticoagulation has shown improved outcomes in retrospective studies and meta-analyses, and is favored when compared to anticoagulation alone or surgical interventions, however there are still no definitive guidelines regarding its routine use. With new treatment modalities such as catheter-directed thrombolysis and surgical embolectomy becoming more widely available, larger studies are needed to show which treatment choice is superior. Regardless, prompt diagnosis can be achieved with POCUS and therapy can be initiated sooner which is proven to improve outcomes and was demonstrated in the case above.