ACE and heart failure: China gradually enters an aging society and the incidence of heart failure with normal ejection fraction (HFNEF) is increasing yearly.[1] These patients account for approximately half of all patients with heart failure (HF).[2–4] Beta-adrenergic receptor blockers, angiotensin-converting enzyme inhibitors (ACEI), angiotensin receptor blockers (ARB), and so on are routinely used to treat HFNEF.