Angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin II type 1 receptor blockers (ARBs) improve prognosis in patients with underlying cardiac disease such as chronic heart failure (CHF), ischaemic heart disease (IHD), and hypertension (HT) [17–23] irrespective of cardiac rhythm at the outset of treatment. This evidence concerns the gene ACE and congestive heart failure.