Arguably, the virus that causes COVID-19 was misnamed. The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) does much more than cause the acute respiratory syndrome central to its name. Awareness of the wide range of symptoms and long-lasting effects of the disease have changed how it is diagnosed and how patients are treated at home and following hospitalization. 

While initially everyone was told to watch for classic symptoms of a respiratory illness—cough, fever, and shortness of breath—those symptoms emerged in the week before a diagnosis with COVID-19 only about twice as often as in people who tested negative for the virus in a study of 77,167 people tested for COVID-19. A loss of smell or taste, however, occurred in 27 times as many people with a positive diagnosis. 

The virus affects the taste and olfactory senses and because it attacks ACE2 receptors, which are present in large numbers in the nose as well as on the tongue. In fact, ACE2 receptors are 200 to 700 times more common in nasal epithelium cells than in the lungs. 

The proclivity for ACE2 receptors also explains why the disease frequently presents in other ways that no one expected for what was thought to be a respiratory virus. And, it provides critical background for the important role that anticoagulants play for some COVID-19 patients who may not fully understand why they have been prescribed the drugs.

A study published in EClinicalMedicine in late June detailed autopsies of seven patients who died of COVID-19. All had platelet-rich blood clots in their pulmonary, hepatic, renal, and cardiac microvasculature, even though some patients had been fully anticoagulated. Cardiac thrombi were present in patients without atherosclerosis, and renal thrombi occurred in patients without other kidney pathology. The study authors suggested that megakaryocytes infected by the virus may travel through the body and producing the blood clots. In the heart, infected vascular endothelial cells, which also have many ACE2 receptors, may also cause clots. 

Hospitals have reported that clots have been clogging dialysis lines in COVID-19 patients with kidney damage, and physicians have watched thrombi form even while they were removing other clots from individuals who suffered a stroke as a result of the virus. Clinicians also report extraordinarily high levels of D-dimer or blood clot fragments in coronavirus patients.

As a result of the prevalence of highly problematic blood clots, many hospitals start the majority of admitted patients on anticoagulants. Guidelines from the American College of Cardiology advocate continuing prophylaxis with either low molecular weight heparin or a direct-acting oral anticoagulant such as apixaban, dabigatran, edoxaban, or rivaroxaban for up to 45 days after discharge for most patients and longer for those at highest risk.
A recent study in the Journal of American College of Cardiology indicated that the use of rivaroxaban could significantly benefit these patients. The study found that 45 days of postdischarge use of drug reduced the risk of venous thromboembolism, stroke, myocardial infarction, and cardiovascular death by 28% without increased risk of major bleeding. 

While the patients in the study did not have COVID-19, the authors said, “We are encouraged by the study’s results to potentially reduce these life-threatening thromboembolic episodes by expanding the use of rivaroxaban for patients post-hospitalization.” In addition, they noted, based on the results, that “Northwell Health has adapted its treatment policy for discharged COVID-19 patients, and others at risk, across the health system.” Northwell Health is a major healthcare system in New York.

Given the serious risk of clotting in COVID-19 patients, your encouragement may save the lives of patients who don’t understand how an anticoagulant can help them recover safely from a “respiratory illness.” 

The content contained in this article is for informational purposes only. The content is not intended to be a substitute for professional advice. Reliance on any information provided in this article is solely at your own risk.

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