Atrial Fibrillation (AF) is the most commonly occurring sustained arrhythmia in clinical practice. AF is a serious disorder associated with an increased risk of stroke, morbidity and mortality, and the number of patients is estimated to double within the next 4 decades. The currently available antiarrhythmic drugs have limited efficacy and are associated with serious side effects of which potentially lethal ventricular proarrhythmias are one of the major concerns. Thus, there is a large unmet clinical need for efficacious and safe antiarrhythmic drugs for the treatment of AF.