Pulmonary embolism in patients with severe COVID-19 treated with systemic low-dose thrombolytic therapy: A case series.

Coronavirus disease 2019 (COVID-19) has been associated with respiratory failure and high mortality. Hypercoagulability and thromboembolic complications have been found in a high percentage of patients amongst which, pulmonary embolism (PE) is the most common. Currently, there are no guidelines on using thrombolysis therapy in COVID-19 patients who developed PE. We present five survivors aged 30-75 years old with confirmed COVID-19. All cases were proven by computed tomography pulmonary angiogram (CTPA) to have PE treated with low-dose recombinant tissue plasminogen activator (rtPA). PE should be suspected in all COVID-19 patients with rapid worsening of dyspnea, desaturation, unexplained shock, and increased level of D-dimer and fibrinogen. In our cases, PE developed despite preventative anticoagulation regimens with low molecular weight heparin. After thrombolytic therapy, all patients showed improvement in partial-arterial-oxygen-pressure to inspired oxygen-fraction ratio (arterial partial pressure of oxygen/inspired oxygen fraction ratio). D-dimer showed elevation after thrombolytic therapy and decreased in the following days. Fibrinogen levels decreased following thrombolytic therapy. Current anticoagulation regimens seem insufficient to halt the course of thrombosis, and thrombolytic therapy may be beneficial for patients with severe COVID-19 and PE. Systemic thrombolysis therapy is a double-edged sword, and clinicians must balance between benefit and risk of bleeding.