A meta-analysis of randomized controlled trials assessed the efficacy of two drug treatments in reducing mortality in heart failure patients.
Chronic heart failure affects 1-2% of the adult population in developed countries and it has one of the highest morbidity and mortality rates for cardiovascular disease globally. It is thus crucial to decrease the risk of adverse clinical outcomes in the therapy of this disease.
It is well known among healthcare professionals that one of the pathophysiological mechanisms of heart failure is the excess activation of a system called renin-angiotensin aldosterone system (RAAS). RAAS is simply a system within our bodies that uses hormones to regulate the amount of water that is reabsorbed back into the body and our blood pressure.
Within the last few years, clinical trials have demonstrated that suppressing RAAS through the use of drug treatments, angiotensin-converting enzyme inhibitors (also known as ACEIs) and angiotensin II receptor blockers (also known as ARBs) decreases cardiovascular events in heart failure patients. However, the effectiveness of inhibiting the RAAS with these two drugs in patients with heart failure still remains unclear.
A meta-analysis of randomized controlled trials was conducted and published in BMC Cardiovascular Disorders in an attempt to assess the efficacy of ACEIs and ARBs in reducing all-cause and cardiovascular mortality in heart failure patients.
This meta-analysis collected clinical trial data from 38 studies, including 47,662 patients with heart failure, in order to assess the effectiveness of these two pharmacological drug treatments on mortality. The major findings were that ACEIs decrease the all-cause mortality by 11% and the equivalent value for cardiovascular mortality by 14%.
On the other hand, ARBs were shown to have no significant effect on all-cause and cardiovascular mortality in patients with heart failure.
By assessing these two drugs from a pharmacological point of view the superiority of ACEIs over ARBs can be explained. ACEIs have an effect by decreasing water reabsorption in the body and by promoting the dilation of blood vessels, anti-inflammation, and anti-fibrosis all of which are positive effects in patients with heart failure.
ARBs, however, do block the RAAS but also can mediate harmful cardiovascular effects of angiotensin II by a compensatory mechanism.
The results clearly indicate that ACEI’s but not ARBs reduce all-cause mortality and death in heart failure patients. This meta-analysis, therefore, highlights that ACEIs should be considered as first-line therapy to decrease the morbidity and mortality in this population of patients.
Reference: Tai.C et al. (2017). Effect of angiotensin-converting enzyme inhibitors and angiotensin II receptor blockers on cardiovascular events in patients with heart failure: a meta-analysis of randomized controlled trials. Available: https://bmccardiovascdisord.biomedcentral.com/articles/10.1186/s12872-017-0686-z. Last accessed 18th Nov 2017.
