Response to Letter Regarding Article, "Upregulation of K2P3.1 K+ Current Causes Action Potential Shortening in Patients With Chronic Atrial Fibrillation". Issue 11 (15th March 2016) - Schmidt, Constanze; Wiedmann, Felix; Voigt, Niels; Zhou, Xiao-Bo; Heijman, Jordi; Lang, Siegfried; Albert, Virginia; Kallenberger, Stefan; Ruhparwar, Arjang; Szabó, Gábor; Kallenbach, Klaus; Karck, Matthias; et al.