A study published in Catheterization & Cardiovascular Interventions found that COVID “appears to have driven a sharp rise in myocarditis cases during the pandemic, and rates have remained elevated ever since.” CIDRAP has the news.
Myocarditis hospitalization rates were relatively stable before the pandemic. They climbed sharply during the pandemic, going from between 67 and 71 cases at the 10 hospitals studied to 103 cases in 2020, 128 in 2021, and 139 in 2022. Population-level analyses found that COVID infection was “tied to a roughly 16-fold increased risk of myocarditis.” After the pandemic began to wane, rates did not return to baseline. This could be because of “persistent cardiac inflammation following a COVID infection, lingering immune system dysregulation, and ongoing circulation of COVID.”
Myocarditis patients also skewed older during the pandemic and were more likely to have cardiometabolic conditions already. Additionally, racial disparities were present, as Black patients were hospitalized more frequently.
Vaccine-related myocarditis, which has been documented but “rare,” was an unlikely contributor to the uptick in hospital cases. The findings in the study “underscore the need for ongoing surveillance and further study to better understand who is most at risk for myocarditis in the post-pandemic period.”
