Next, we assessed A2AR mRNA expression in PBMCs from ndSR, dSR and AF patients through RT-qPCR analysis A three-fold significant increase in A2AR mRNA expression in PBMCs from AF patients was found (p < 0.0001, F(2, 24) = 14.64) (Figure 4B). Here, ADORA2A is linked to atrial fibrillation.