Effect of Hyperthyroidism on Delayed Rectifier K+ Currents in Left and Right Murine Atria

摘要

Changes in thyroid status can lead to dramatic alterations in the electrophysiological properties of the myocardium (1-3). A consistent finding is that hyperthyroidism results in higher heart rate while hypothyroidism lowers heart rate. In addition, the hyperthyroid heart has an increased propensity for atrial arrhythmias especially atrial fibrillation (AF) which is observed in 10-15% of patients with hyperthyroidism (4-5). Furthermore, unexplained atrial fibrillation observed in 13% of patients is due to unrecognized hyperthyroidism (6). The electrophysiological and molecular mechanisms underlying these changes are only incompletely explored. Mechanism resulting in hyperthyroidism induced increases in heart rate and the increased propensity for AF is briefly reviewed.