Q: Should I be worried about reports of heart problems after receiving my COVID-19 vaccine?
A: Several cases of myocarditis (inflammation of the heart tissue) after receiving one of the mRNA vaccines have been logged by the Vaccine Adverse Event Reporting System and are currently under review. Similar reports previously surfaced in the U.S. military as well as from an Israeli study.
Both Pfizer and Moderna produce mRNA vaccines, short for messenger RNA. This new type of vaccine teaches the body's cells to make a protein that triggers an immune response.
Most people affected by myocarditis are young males presenting to their physicians with chest pain, shortness of breath and an irregular heart rate, and most of their symptoms resolve after rest and anti-inflammatory medicine.
In a recent case series of seven adolescents diagnosed with myocarditis after receiving their second mRNA vaccine, the authors concluded that a causal relationship could not be determined — particularly given the seasonal prevalence and the sex and age profile of background cases of myocarditis in this population during the observation period. A biological mechanism is not yet known but could be secondary to the body's immunological response, similar to what causes other known adverse effects after vaccination like fever, chills and general malaise.
As of May, 2.5 million doses of Pfizer have been given to 12- to 15-year-olds and 4 million to 16- to 18-year-olds in the United States, according to the American Academy of Pediatrics. Data from the Centers for Disease Control and Prevention surveillance systems report 277 cases of myocarditis in the 12- to 24-year-old age groups during this time. This group has received almost 9% of total doses but represent more than half of the total observed cases of all age groups. A relationship between vaccination and myocarditis, however, has not been established, and the CDC continues to recommend vaccination for everyone 12 or older.
Over 4 million COVID-19 cases in children less than 18 years of age have been reported, 15,000 hospitalizations and almost 600 deaths. The benefit of vaccination in this population far exceeds the risk of rare adverse events.
The CDC and the Advisory Committee on Immunization Practices are scheduled to meet later this week to review these findings and assess the benefit/risk ratio to provide further recommendations. Clinicians who suspect myocarditis should consider consulting with a pediatric cardiologist and informing the Vaccine Adverse Event Reporting System.
Fernando Urrego, M.D,, is the interim health officer at the Hamilton County Health Department and a member of the Chattanooga-Hamilton County Medical Society.