Role of the angiotensin II receptor blocker valsartan in heart failure.

Despite an enormous amount of research carried out in the past 10 to 20 years, the role of the renin-angiotensin system in the development of heart failure is still not very well understood. This review looks at preclinical data on the role of angiotensin II as a circulating and local hormone, and the effects of stimulation of the respective receptors in heart tissue. Recent large scale clinical trials have begun to furnish evidence of the effects of blocking the renin-angiotensin system in patients with heart failure using angiotensin-converting enzyme inhibitors or, more recently, angiotensin II receptor blockers that act directly at the receptor level, independent of pathways for angiotensin II generation. Results so far indicate that there are benefits from optimizing the blockade, but open questions remain, such as the role of endothelin and bradykinins, and the extent of crosstalk between the different systems.