Understanding of thrombotic complications in COVID-19 patients evolves

Sameep Sehgal, MD

The COVID-19 knowledge base has evolved quickly during the pandemic. The Wednesday, October 21 morning session, Help! My Patient Is Clotting: COVID-19-related Coagulopathy, reviewed emerging data on the prevalence, nature, and pathophysiology of thrombotic complications related to this novel disease.

The session is available for on-demand viewing on the virtual CHEST 2020 meeting platform through January 18, 2021, for registered attendees.

Sameep Sehgal, MD, assistant professor of thoracic medicine and surgery at Temple University, gave an overview of the latest insights into the epidemiology of thrombotic complications in patients with COVID-19. An analysis of several studies on the topic shows that thrombosis is common in COVID-19 patients, he said, occurring in about 30% of those in the ICU and in about 13% of those hospitalized outside of the ICU. Arterial thrombosis is less prevalent but relatively common, especially in sicker patients.

The timing of thrombosis presentation can vary from early to several weeks after COVID-19 symptoms appear. Compared to other viral diseases, severe COVID-19 cases may be more likely to experience thrombosis, Dr. Sehgal said.

Parijat Sen, MD, MBBS

“I think there’s likely a higher incidence than [in] other severe viral diseases,” Dr. Sehgal said. “I’m not sure that mild or moderate diseases, or mild or moderate COVID-19, presents a higher risk of thrombosis. This may change down the road as we get more prospective studies through this fall and winter.”

Thrombosis in COVID-19 patients is associated with increased mortality and can be an unsuspected cause of death, he continued.

“Autopsies have consistently shown that the incidence of thrombotic events in COVID-19 patients is pretty significantly high, be it in forms of venous thromboembolism, or myocardial venous thrombosis, or vasculitis,” said Parijat Sen, MD, MBBS, assistant professor, division of pulmonary and critical care at the University of Kentucky. He presented on the pathophysiology of coagulopathy in patients with COVID-19.

“Hypercoagulability in COVID-19 is multifactorial secondary to hyperviscosity due to high fibrinogen levels, very high platelet-rich thrombi with presence of lupus anticoagulant, and definitely impaired fibrinolysis,” Dr. Sen explained.

Shruti Gadre, MD

Shruti Gadre, MD, critical care physician and transplant pulmonologist at the Cleveland Clinic, addressed the management options and recommended treatment strategies for COVID-19 patients with thrombosis.

Based on the currently available data, there is no role for routine surveillance screening for venous thromboembolism in patients with COVID-19, she said, but cautioned that physicians should have a high index of suspicion.

Standard-dose thromboprophylaxis with either unfractionated heparin or enoxaparin is recommended for all COVID-19 patients admitted to the ICU, Dr. Gadre said.

“Therapeutic-dose anticoagulation is the treatment of choice for patients with venous thromboembolism,” she added. “There are no data to support routine extended thromboprophylaxis, but it may be feasible to employ that in certain patients.”

Several clinical trials are underway in various stages of enrollment to further the understanding of thrombotic complications in COVID-19 patients.