A new study of U.S. service members found higher than expected rates of heart inflammation following receipt of COVID-19 vaccines. It's a finding Defense Department researchers say should call attention to the condition, known as myocarditis, as a potential side effect of the immunizations.In an article published Tuesday in JAMA Cardiology, U.S. Army, Navy and Air Force physicians described 23 cases of myocarditis in previously healthy males who developed the condition within four days of receiving a COVID-19 vaccine.Physicians would have expected to find eight or fewer cases of myocarditis among the 436,000 male military members who received two mRNA...