The risk of developing myocarditis and other inflammatory heart conditions after COVID-19 vaccination is substantially lower than it is after SARS-CoV-2 infection, according to an analysis of electronic health records from 40 US health systems.
Although it’s a rare complication, myocarditis has been associated with both SARS-CoV-2 infection and messenger RNA (mRNA)–based vaccines against the virus. To directly compare the likelihood of developing it and other cardiac complications after vaccination vs infection, the investigators calculated incidence rates of myocarditis; myocarditis or pericarditis; and myocarditis, pericarditis, and multisystem inflammatory syndrome (MIS) among 15.2 million people treated in health systems that participated in the National Patient-Centered Clinical Research Network from early January 2021 through January 2022.