Providing end-organ protection with renin-angiotensin system inhibition: the evidence so far

Much debate surrounds the question of the optimal therapeutic choices for medication to control blood pressure and reduce cardiovascular events. Experimental evidence suggests that drugs that block the renin-angiotensin system retard vascular disease through their direct ability to antagonize the effects of angiotensin II, which has vasoconstrictive, vascular proliferative, and atherosclerotic effects. It is not known how to separate the potential vascular protective effects of the drugs from their antihypertensive benefits. Clinical trial evidence indicates that achieved lower blood pressure goals almost always confer cardiovascular risk reduction advantages. There is also evidence, however, that successful antihypertensive regimens incorporating a renin-angiotensin system blocker, such as an angiotensin-converting enzyme inhibitor or an angiotensin receptor blocker, provide more cardiovascular risk reduction benefit compared with regimens that do not incorporate a renin-angiotensin blocker. This includes composite or specific end points involving reduction of stroke, myocardial infarction, or development of end-stage renal disease.