IL6 and atrial fibrillation: There was no significant difference in AF IL-6 among CSTs (CST I: median 214 pg/mL [50–327]; CST III: median 1516 pg/mL [186–10000]; CST IV-A: median 2174 pg/mL [68–10000] and CST IV-B: median 1242 pg/mL [118–10000]); (p = 0.18; Fig 5).