A new study published in the Journal of the Irish Medical Organisation has examined cardiac investigations in children who experienced chest pain after receiving a Covid vaccine.
The study, conducted by the Department of Paediatric Emergency Medicine, Children’s Health Ireland, Tallaght Hospital, looked at a total of 30 children who had received a Covid vaccine dose.
Authors noted that paediatric patients had presented at the Emergency Department (ED) at the Dublin Hospital following COVID-19 mRNA vaccination.
The retrospective study aimed to determine both the safety and efficacy of current guidelines for investigating chest pain in the aftermath of COVID-19 mRNA vaccination. It assessed the data over an 11-month period, between August 2021 (when vaccinations for paediatric patients aged between 12-15 years first began in Ireland) to June 2022.
In total, 30 patients met the criteria for involvement in the study. 77 per cent of participants (23) were male.
Researchers noted that 17 (57%) patients reported symptoms after the second dose vaccine, while 13 (43%) patients after the first dose. Regarding investigations performed, all patients had an ECG performed and reviewed in the ED. 28 patients (93%) had a troponin level performed in the ED.
Only 20 patients (67%) had a chest radiograph, and 12 patients (40%) had a creatine kinase level measured in the ED. Authors said that initial investigations of ECG and troponin would be “key in informing whether specialist referral and further investigations such as echocardiogram or cardiac MRI are necessary.”
The authors said that there had been “reports of pericarditis and myocarditis in some adult cases,” adding that cases are rare, with the overall UK estimate being 10 myocarditis cases per million doses of the Pfizer vaccine, and 7 pericarditis cases per million doses of the Pfizer vaccine,
Vaccine-related myocarditis, particularly after mRNA COVID-19 vaccines, is thought to result “from an immune-mediated response, possibly involving molecular mimicry, where the immune system mistakenly targets heart tissue”, they said.
Most cases have been observed in male adolescents and young adults, typically within a weekof the second vaccine dose, authors said, while noting symptoms such as chest pain and elevated cardiac biomarkers.
“The condition is usually mild and self-limiting, with most patients fully recovering after supportive care,” the Irish study adds.
Authors continue: “Studies from countries like the U.S and Canada confirm a small but real risk of myocarditis, especially in younger males, though its incidence remains rare. Despite this risk, vaccination is crucial, as COVID-19 itself poses a higher risk of myocarditis and severe complications.
“There is limited research on Ireland’s paediatric population, which may have unique demographic factors influencing outcomes. Filling this gap would contribute to better understanding vaccine safety in children and support national public health efforts.”
They continued to note that evaluating children with chest pain following mRNA COVID vaccination can be “challenging.”
“There are interim guidelines from several centres regarding the investigation of patients who present with new onset chest pain, shortness of breath, syncope, palpitations or dizziness shortly following mRNA vaccination for COVID-19,” the study says.
It adds that the primary aim of the research was to investigate the department’s compliance with performing the recommended investigations in this sub-group of patients – while the secondary aim was to assess if any of these investigations were consistently abnormal.
For the research, a single centre retrospective study was performed at Tallaght University Hospital, assessing the data over a 11 month period between August 2021 and June 2022.
This study included all patients within the 12-15 year age group, presenting with new-onset chest pain, shortness of breath, syncope, palpitations or dizziness within 6 weeks of COVID- 19 mRNA vaccination (either first of second dose). Researchers excluded any patient younger than 12 years or older than 15 years of age, or those with chest pain not related to COVID-19 vaccination or any other pre-existing medical condition.
Recording the results, authors wrote: “Our study showed that there has been 100% compliance with performing ECG for all patients who presented with new-onset chest pain or cardiac symptoms following Covid mRNA vaccination. In our study, none of the investigations were severely deranged or abnormal. Clinical follow-up of the patients revealed that the vast majority had a mild, self-limited period of symptoms which resolved a few days later.
“All of the patients who had reported symptoms after the first vaccine, chose to receive their second Covid vaccine and reported no recurrence of symptoms thereafter.”
They noted that, in general, male populations are at a higher risk of developing pericarditis or myocarditis after vaccination. Symptoms are also more prevalent after the second dose of COVID-19 vaccine.
“Given that all patients in our study experienced mild, self-limited symptoms and opted for their second vaccine dose without recurrence of symptoms, this supports the safety of continued vaccination even in those who experience initial side effects,” the findings noted.
“These results can inform future guidelines by reinforcing that routine cardiology referrals may not be necessary when initial investigations are normal, streamlining patient management and reducing unnecessary healthcare burdens. Additionally, the study highlights the need for ongoing monitoring of at-risk populations, such as males and those receiving second doses, while ensuring continued public confidence in vaccine safety.”
Authors acknowledged a number of limitations to the study:
“The retrospective nature of the study may also introduce biases due to incomplete medical records. As the sample was small and drawn from a single hospital over a limited period, the conclusions may not fully capture the broader population, particularly in different geographical or demographic contexts.
“Larger, multi- centre studies would be necessary to confirm these findings and strengthen the evidence for widespread vaccination safety protocols, especially in diverse settings. Nevertheless, our results offer a foundation for refining post-vaccine monitoring and may inform broader vaccination efforts, but should be interpreted with caution due to these limitations.”
In conclusion, researchers wrote that initial investigations of ECG and troponin level are “key in informing whether specialist referral and further investigations such as echocardiogram or cardiac MRI are necessary.”
They added that chest radiograph should be considered in individual cases when seeking other differentials or if assessing for pericardial effusion. In addition, they noted that creatine kinase measurement has not been a routinely recommended investigation of choice by the international guidelines.