Nonthyroidal Illness Syndrome in Cardiac Illness Involves Elevated Concentrations of 3,5-Diiodothyronine and Correlates with Atrial Remodeling

Background: Although hyperthyroidism predisposes to atrial fibrillation, previous trials have suggested decreased triiodothyronine (T<sub>3</sub>) concentrations to be associated with postoperative atrial fibrillation (POAF). Therapy with thyroid hormones (TH), however, did not reduce…