Renin-angiotensin system blockade and cardiovascular and renal protection

The renin-angiotensin-aldosterone system (RAAS) plays an important role in the pathogenesis of a variety of clinical conditions, including atherosclerosis, hypertension, left ventricular hypertrophy, myocardial infarction, and heart failure. Inhibition of the RAAS with either angiotensin-converting enzyme inhibitors or angiotensin receptor blockers (ARBs) has been shown to be effective in lowering blood pressure and reducing cardiovascular mortality and morbidity in various at-risk patient populations. A number of studies have shown that these 2 classes are effective in reducing the rate of renal disease progression in patients with diabetic nephropathy, although more long-term vascular outcome studies are needed in patients with chronic kidney disease. The Ongoing Telmisartan Alone and in Combination with Ramipril Global Endpoint Trial (ONTARGET) was the first study to show comparable reno- and cardioprotective effects between an ARB (telmisartan) and ramipril in a broad section of at-risk patients, on top of usual standard care. However, telmisartan showed better tolerability than ramipril in ONTARGET, with less cough and angioedema. This difference was obtained despite patients having been selected for tolerability to both drugs at study entry.