Guidance on Treatment for Rare Blood Clots, Low Platelets Related to COVID-19 Vaccine

The AHA released a report to provide guidance about CVST, TTS, and VITT after receiving the COVID-19 vaccine.

The American Heart Association released a special report, “Diagnosis and Management of Cerebral Venous Sinus Thrombosis with Vaccine-Induced Immune Thrombatic Thrombocytopenia,” to provide important guidance about cerebral venous sinus thrombosis (CVST), thrombosis-thrombocytopenia syndrome (TTS), and vaccine-induced immune thrombotic thrombocytopenia (VITT) after receiving the COVID-19 vaccine.

“COVID-19 infection is a significant risk factor for CVST. A preliminary analysis of US data during the COVID-19 pandemic, available online, preprint on April 15, 2021, found that the risk of CVST due to infection with COVID-19 is 8-10 times higher than the risk of CVST after receiving a COVID-19 vaccine,” said Karen L. Furie, MD, MPH, lead author of the special report, in the press release. “The public can be reassured by the CDC’s and FDA’s investigation and these statistics—the likelihood of developing CVST after a COVID-19 vaccine is extremely low. We urge all adults to receive any of the approved COVID-19 vaccines.”

The analysis included data from 59 health care organizations and 81 million patients, more than 98% of whom were in the United States. Out of approximately 514,000 patients in the database who were diagnosed with COVID-19 infection from January 20, 2020, through March 25, 2021, 20 patients were diagnosed with CVST. These data were compared to the incidence of CVST in adults who received either the Pfizer or Moderna COVID-19 vaccine before March 25, 2021, excluding those who had been previously diagnosed with COVID-19.

“CVST blood clots are very rare adverse events. We recommend immediate screening of all patients who arrive in the ER with a suspected clot—did they receive a COVID-19 vaccine during the recent weeks prior to this event?” Furie said in the press release. “Patients who present with the symptoms of CVST or blood clots and who recently received the COVID-19 vaccine should be treated using non-heparin anticoagulants. No heparin products in any dose should be given for suspected CVST, TTS or VITT. With the right treatment, most patients can have a full recovery after CVST, TTS or VITT.”

Some of the highlights of the report include:

  • All patients with suspected CVST due to a COVID-19 vaccine should be treated with non-heparin anticoagulants, such as argatroban, bivalirudin, danaparoid, fondaparinux, or a direct oral anti-coagulant.
  • Blood tests should include a complete blood count.
  • Magnetic resonance imaging with a venogram or computed tomography with venogram is recommended to accurately detect and diagnose CVST.

“We are learning the various intricacies of COVID-19 live, in real-time with the patients we see in our hospitals every day. CVST is extremely rare, however, further research and investigation are necessary as the pandemic continues. We will need data and robust research on the people who did not develop blood clots after the vaccine, too, so that we can fully understand the molecular and cellular mechanisms underlying CVST related to COVID-19 infection or after vaccination,” Furie said in the press release.