Angiotensin Receptor Blockers versus Angiotensin-Converting Enzyme Inhibitors: Where Do We Stand Now?

Cardiovascular disease represents a continuum that starts with risk factors, such as hypertension, and progresses to atherosclerosis, target organ damage, and ultimately leads to heart failure or stroke. Renin-angiotensin-aldosterone system (RAAS) blockade with angiotensin-converting enzyme (ACE) inhibitors or angiotensin receptor blockers (ARBs) has been shown to be beneficial at all stages of this continuum. Both classes of agent can prevent or reverse endothelial dysfunction and atherosclerosis, thereby potentially reducing the risk of cardiovascular events. Such a reduction has been shown with ACE inhibitors in patients with coronary artery disease, but no such data are currently available for ARBs. Both ACE inhibitors and ARBs have been shown to reduce damage in target organs, such as the heart and kidney, and to decrease cardiovascular mortality and morbidity in patients with congestive heart failure. Trials, such as the Ongoing Telmisartan Alone in Combination with Ramipril Global Endpoint Trial (ONTARGET) and the Telmisartan Randomised Assessment Study in ACE-Intolerant Subjects with Cardiovascular Disease (TRANSCEND), that compare telmisartan, ramipril, and their combination in high-risk patients with vascular end-organ damage, should provide important new insights into the benefits of intervention with RAS blockade along the cardiorenovascular continuum.