The use of renin–angiotensin system blockers (angiotensin‐converting enzyme inhibitor/angiotensin‐receptor blocker) was related to a decrease of AF in a the subanalyses of several RCTs,569, 570, 578, 579 but the effect of a single intervention, so‐called “upstream therapy”, has been denied.235, 552, 580. This evidence concerns the gene ACE and atrial fibrillation.