ORAI1 and Arrhythmia: Other recent works suggested that SOCE mediated by Orai1 interaction with STIM1 modifies heart rate by pacemaker stimulation (Zhang H. et al., 2015), and plays a role in the initiation of arrhythmias in both atrial and ventricular myocytes (Wolkowicz et al., 2011; Wang et al., 2012).