Ioannis Katsoularis and colleagues1 found that COVID-19 is a risk factor for myocardial infarction and stroke through self-controlled case series evaluation, a method that has been used to establish the risk of myocardial infarction associated with influenza infection.2, 3 Regarding myocardial infarction, as the investigators recognised, one of the possible limitations of this research is the inaccurate diagnosis and codification of myocardial injury or myocarditis as myocardial infarction, particularly because the current myocardial infarction definition (and diagnostic methods) differ from the definition at the time of the registry outcome validation study.4 In this context, we would like to stress that it is important to report either the risk estimates for ST-segment elevation myocardial infarction similarly to previous influenza studies,5 or the risk of coronary revascularisation procedures after COVID-19, to decrease the potential bias and increase the robustness of the data and conclusions.

© 2021 Barbara Gindl/APA/AFP/Getty Images
We declare no competing interests.
References
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