Role of angiotensin-converting enzyme inhibitors in vascular modulation: beyond the hypertensive effects

Angiotensin-converting enzyme (ACE) inhibitors are being widely used as antihypertensives by clinicians worldwide. One in every three Americans has hypertension. Hypertension, diabetes, obesity, active smoking, hypercholesterolemia, and inactivity are the major cardiovascular risk factors, which can produce compounding effects on human health, leading to cardiovascular morbidity and mortality. We review the mechanism of action of ACE inhibitors and explain the rationale for using ACE inhibitors not only in hypertensive patients but also in patients with congestive heart failure, acute myocardial infarction, or coronary artery disease. ACE inhibitors can reduce preload and afterload on the heart, prevent ventricular remodeling, and even retard atherogenic changes in the vessel walls. ACE inhibitors can also be helpful in slowing the progression of kidney disease, especially in diabetics. Some studies such as the Heart Outcomes Prevention Evaluation study have shown that ACE inhibitors can reduce the risk of cardiovascular morbidity and mortality, particularly in high-risk individuals. The renin-angiotensin-aldosterone system plays an important role in regulating blood pressure and body volume in the human body. ACE inhibitors and angiotensin-receptor blockers are the two classes of antihypertensives that primarily act on the renin-angiotensin-aldosterone system. We discuss randomized, controlled trials that evaluated different ACE inhibitors and compare them with angiotensin-receptor blockers.