Prevalence of AF is usually higher in patients with chronic renal impairment probably because of the increased sympathetic tone and renin‐angiotensin‐aldosterone system activation which, in turn, cause atrial electrical and structural remodeling.40 The predictive value of the score for risk of AF recurrence after cardioversion in patients with chronic kidney disease, however, has never been reported before. Here, REN is linked to chronic kidney disease.