Lastly, low-level but long-standing subtlecortisol excretion may have direct toxic effect on myocardium by glucocorticoidreceptors leading to myocardial fibrosis.4-6,13,29Detection of prolonged atrial EMD in these patients may be an earlier sign of atrialdysfunction preceding AF. The gene discussed is NR3C1; the disease is Myocardial fibrosis.