Researchers have published a study showing persistent cardiac MRI findings in young males following inoculation with COVID mRNA vaccines and call for more multicentre studies to determine the “ultimate clinical significance” of post-vaccine myopericarditis.

Published in the Journal of Pediatrics, the study details the cardiovascular effects and, in particular, effects of myocarditis on 35 patients (reduced to 16 due to patients not following up, following up out of state, that a study is still pending, or CMR imaging occurred too late). All patients had been diagnosed with myopericarditis following inoculation with the Pfizer COVID-19 mRNA vaccine.

“Myopericarditis has emerged as an important adverse event following COVID-19 mRNA vaccination, particularly in adolescents. Patients typically exhibit chest pain and an elevated serum troponin level in the days following the COVID-19 mRNA vaccine. They usually are hemodynamically stable, and symptoms and cardiac biomarkers normalize within a few days,” the researchers begin.

“Cardiac magnetic resonance [CMR] studies, when performed early, frequently demonstrate abnormalities such as edema and late gadolinium enhancement (LGE), meeting Lake Louise Criteria for diagnosing myocarditis noninvasively.”

“In classical myocarditis LGE can be predictive of a poor outcome. Little is known about the prognostic value or expected evolution of these CMR abnormalities associated with post-COVID-19 mRNA vaccine myopericarditis…”

According to researchers, 62.5 per cent of patients had an abnormal electrocardiogram, and two patients demonstrated “mildly reduced [left ventricle] systolic function with no dilation.

As per the results of the study, all patients who came in with myocarditis received cardiovascular magnetic resonance imaging.

“All were abnormal; all showed evidence of edema [swelling from inflammation] by T2 imaging, and 15/16 had LGE [myocardial late gadolinium enhancement] in a patchy subepicardial to transmural pattern with predilection for the inferior [left ventricle] free wall,” researchers write.

Patients were subsequently treated — mostly with ibuprofen every 8 hours. Of the 16 who followed up 3-8 months later, most CMRs showed that symptoms and abnormalities had significantly improved when. However, eleven patients had persistent myocardial late gadolinium enhancement (LGE).

This is profound. According to a meta-analysis published by the American Heart Association, LGE-positive patients have a 2.7 times higher mortality rate when faced with cardiovascular problems.

“Patients with LGE had increased overall mortality, heart failure hospitalization, and SCD/aborted SCD compared with those without LGE. The annualized event rates for mortality were 4.7% for LGE+ subjects versus 1.7% for LGE− subjects, 5.03% versus 1.8% for heart failure hospitalization, and 6.0% versus 1.2% for SCD/aborted SCD,” the study reads.

Researchers in the first study concluded that the adverse effects of mRNA vaccines warrant “follow-up assessment and larger multicenter studies” to determine the “ultimate clinical significance of persistent CMR abnormalities in patients with post-COVID-19 vaccine myopericarditis.”