How rare are ER visits for children with chest pain, post mRNA vaccine?

Peer reviewed study from Australia, Sept, 2023

As a sometime-ER physician, I was interested in learning more about how children’s hospitals experienced the mRNA vaccine rollout in adolescents and children in 2021. I was not working in emergency medicine at the time, so was unable to observe what was happening in terms of adverse reactions. Conversations with a couple of ER colleagues revealed no great interest or observations on the issue.

A September 2023 peer-reviewed publication of an Australian children’s ER experience on the question was thus most welcome. It left some questions, meanwhile.

This study explores data from 2021, using review of medical records. Authors were able to link emergency department records with immunization records, which is the single outstanding feature of this paper. Their window of observation was a troponin blood test performed within 14 days of receiving mRNA vaccine.

The majority of troponin tests that were drawn for children visiting the ER in Royal Children’s Hospital in Melbourne, Australia in 2021 were related to mRNA vaccine presentations (283 out of 359 tests). 14 of these 283 troponins were abnormal. These were judged as being cases of mRNA myocarditis.

The authors do not calculate the incidence rate of mRNA vaccine myocarditis based on their results, however we can estimate this based on a youth population in Greater Melbourne of 500K with a 90% vaccination rate, thus 14 cases in 450K exposures, or 30 cases per million. This represents a low estimate, meanwhile.

The article mentions a September 2021 clinical bulletin that recommended any post-vaccine patient presenting with chest symptoms to have a troponin blood test.

I was unaware of a clinician education campaign about possible myocarditis in Australia in 2021. The reference link in the article gives a 404 error (reference 8).

An additional issue is what the “miss rate” (aka sensitivity) of troponin might be for myocarditis. This research letter from 2023 found a 7% rate of myocarditis seen on cardiac MRI with a normal troponin. In the ER study, this could translate into an additional 21 cases of myocarditis, more than doubling the findings in the study.

UNANSWERED QUESTIONS

1. how many abnormal ECGs were recorded?

2. what was total number of presentations to this children’s hospital ER for chest pain?

3. what was total number of presentations for any reason within 2 weeks of vaccination?

4. what is the role of cardiac MRI as a screening test for suspected myocarditis, if troponin is normal?

It appears that the authors have said their peace, however—

CONCLUSION:

It appears that the mRNA vaccine rollout in children and adolescents was something of an event after all, in terms of children with chest symptoms, in one ER in a large Australian children’s hospital. Meanwhile, they did not record any deaths or ICU cases.