ACE and heart failure: Angiotensin-converting enzyme (ACE) inhibitors are one of the most commonly used medication among patients with arterial hypertension (AH), also the key medication for congestive heart failure and proteinuria in diabetic and nondiabetic nephropathy.[1] For instance, ACE inhibitors are prescribed in 65% of patients with coronary artery disease and in 71% of patients with heart failure.[2] Although ACE inhibitors are well established, medication side effects may present.