FGF23 and Myocardial fibrosis: Switching of Th1 to Th2 polarity is believed to be important during the recovery phase after acute myocarditis, and dysregulation of Th1/Th2 responses has been proposed as a possible cause of post-myocarditic dilated cardiomyopathy.48 Other markers that differed in MRI(+) individuals included ST1A1 and FGF-23, which have also been associated with worse outcomes after MI49 and asymptomatic COVID-19.50 Specifically, FGF-23 is involved in tissue repair, and its elevation could potentially be linked to myocardial fibrosis.