Abstract
We have thoroughly reviewed the research conducted by Marina et al., titled "Acute Myocarditis and Pericarditis After mRNA COVID-19 Vaccinations—A Single-Centre Retrospective Analysis" [1]. We commend the authors for their diligent work in presenting a concise and informative report. While we agree with the overall findings of the study, which indicate a moderate risk of myopericarditis following mRNA COVID-19 vaccinations, particularly among young males, we would like to draw attention to several areas where the conclusion could have been strengthened. Firstly, it is crucial to acknowledge that retrospective studies possess inherent limitations such as recollection bias and potential inaccuracies in patient documentation. These issues could have been mitigated by including actual cases from the relevant period. Additionally, conducting the study across multiple hospitals or utilizing national databases would have helped address any bias arising from distinct socioeconomic, health, and environmental factors [2].
To the Editor,
Secondly, we propose that the authors should have considered clinical comorbidities as research variables. By incorporating binary variables (present or absent) for comorbidities such as chronic obstructive lung disease, ischemic heart disease, diabetes mellitus, inflammatory bowel disease, heart failure, atrial flutter or fibrillation, malignancy, and renal failure—identified through hospital-registered ICD-10 codes—a deeper understanding of the relationship between mRNA vaccinations and myopericarditis could have been attained3. Thirdly, the study failed to account for the 28-day risk window following the first and second vaccine doses3. This temporal data would have played a significant role in estimating the risk of myopericarditis among vaccine recipients. Furthermore, it should be noted that the authors did not address the underlying mechanism behind myocarditis and pericarditis following mRNA vaccination. It is important to recognize that myocarditis can occur even in the absence of a live virus, indicating a potential molecular mimicry and immune-mediated mechanism4. Including a discussion on this mechanism in the study's conclusions would have enhanced its overall value.
Overall, we appreciate the authors' dedication in conducting this research and disseminating their findings. Addressing the aforementioned issues would have bolstered the study's conclusion and provided valuable insights into the relationship between mRNA vaccines and myopericarditis.
Uncited References
Declaration of Competing Interest
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Acknowledgments
Funding
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Acknowledgment
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References
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