ACE and heart failure: The prevalence of HF is age-dependent, ranging from <2% of people younger than 60 years to >10% of those older than 75 years.[4] As a result of ageing of the general population and improved treatment of acute cardiovascular events, the prevalence of heart failure is projected to increase by 25% in the next 20 years.[4] Several drugs have been applied to HF, such as β blockers, calcium-channel blockers, angiotensin-converting enzyme (ACE) inhibitors, and angiotensin receptor blockers (ARBs), but there was no obvious efficacy.[6–9]