Myocarditis cases related to a COVID-19 infection are associated with a much higher risk of death and other adverse outcomes than other cases of myocarditis, according to a new study published in Current Problems in Cardiology.[1]
“Research has shown that infection with COVID-19 affects multiple organ systems, including the cardiovascular system,” wrote first author Harmon Cannon, DO, with the University of New Mexico Health Sciences Center in Albuquerque, New Mexico, and colleagues. “In one study, cardiac complications were found in 20-30% of patients with COVID-19 and were linked to worse patient outcomes. Currently, large-scale studies evaluating outcomes in patients with COVID-19-related myocarditis are limited.”
Cannon et al. examined the National Inpatient Sample database, focusing on data from nearly 18,000 adult patients who were hospitalized in 2020. While 64% of patients presented with COVID-related myocarditis, the remaining 36% of patients presented with myocarditis, but no COVID-19 infection.
Overall, in-hospital mortality was much higher for patients with COVID-related myocarditis (30.7%) than those with a regular case of myocarditis (6.4%). COVID-related myocarditis was also associated with a longer mean length of stay (11.8 days vs. 6.4 days), higher mean hospitalization costs ($180,405 vs. $127,184) and fewer surviving patients who could be discharged directly to their homes (52% vs. 78%). The rates of vasopressor use, mechanical ventilation use, sudden cardiac arrest and acute kidney injury were all also higher for the patients with COVID-related myocarditis.
Meanwhile, the rates of cardiogenic shock and the use of mechanical circulatory support were not significantly different between the two patient groups.
“Prior studies have noted that cardiogenic shock was the most common presenting symptom in patients with COVID-19 myocarditis … we now have significant data showing that the majority of patients with COVID-19 related myocarditis do not present in cardiogenic shock and do not require mechanical circulatory support at higher rates compared to patients with myocarditis without COVID-19 infection,” the authors wrote. “Despite this, we have found they have higher in-hospital mortality, which could be attributed to non-cardiac factors such as septic shock as patients with COVID had higher rate of vasopressors use. Relying on cardiogenic shock as an indicator of Myocarditis in COVID-19 patients may not be as beneficial as once thought.”
The researchers did note that this 2020 outcomes data is from before COVID-19 vaccination had spread throughout the U.S. population.
Michael has more than 16 years of experience as a professional writer and editor. He has written at length about cardiology, radiology, artificial intelligence and other key healthcare topics.