Myocarditis is the name given to inflammation of the muscle tissue of the heart or myocardium and is a condition that can interfere with the functions of this organ and reduce its ability to pump blood and cause symptoms such as chest pain, arrhythmias (fast and irregular heartbeat) and feeling short of breath. After vaccination against COVID-19 began, an increase in cases of myocarditis was observed, especially among adolescent and young men who had received the mRNA vaccines.
In fact, in July 2021, the European Medicines Agency (EMA) recommended including myocarditis and pericarditis as side effects of the Pfizer and Moderna mRNA vaccines, although specifying that this only occurred in very rare cases. However, it was not known what triggered this adverse reaction, but now a team of researchers from Yale University has identified the immune signature of these cases of heart inflammation.
The researchers have published the conclusions of their study in the journal Science Immunology and rule out some of the theoretical causes of heart inflammation, in addition to suggesting potential ways to further reduce this rare side effect of coronavirus vaccines.
Increased risk of myocarditis in unvaccinated people who contract COVID
The US Centers for Disease Control and Prevention (CDC) found that about 22 to 36 out of 100,000 males ages 12 to 17 experienced myocarditis within 21 days of receiving a second dose of the mRNA-type vaccine. , which were designed to generate immune responses specifically against SARS-CoV-2. The incidence of myocarditis among unvaccinated men in this age group was 50.1 to 64.9 cases per 100,000 after infection with this coronavirus.
“I hope that this new knowledge will allow further optimization of mRNA vaccines, which have tremendous potential to save lives in many future applications”
The Yale scientists conducted a comprehensive analysis of immune system responses in these rare cases of myocarditis among vaccinated people and found that the inflammation of the heart was not caused by antibodies generated by the vaccine, but by a more generalized response in the immune cells and inflammation were involved.
“These people’s immune systems go into overdrive and overdrive cellular and cytokine responses,” said Carrie Lucas, an associate professor of immunobiology and one of the team leaders, along with Akiko Iwasakiprofessor of immunobiology, and Inci Yildirim, associate professor of pediatrics and epidemiology at Yale.
Previous research had suggested that increasing the time between vaccine doses from four to eight weeks might decrease the risk of developing myocarditis. Lucas has explained that according to the findings of the CDC the risk of myocarditis is significantly higher in unvaccinated people who become infected with SARS-CoV-2 than in those who receive the vaccines and has highlighted that vaccination offers the best protection against illnesses related to COVID-19.
“I hope that this new knowledge will allow further optimization of mRNA vaccines that, in addition to offering clear health benefits during the pandemic, have tremendous potential to save lives in numerous future applications”, concludes the Dr Anis Barmadaa student at Yale Medical School, who co-authored the paper with Dr. Jon Klein, who is also a student at the center.
.
