s-metoprolol for hypertension and heart failure

Although theoretically 3rd generation beta blockers such as nebivolol are supposed to be more advantagious over cardioselective ones due to their additional vasodilating property because of action on alpha receptors, Randomized Controlled trials have failed to show their additional benefits. Since s-metoprolol has more benefits compared to r isomer, it can be predicted that it would be advantagious over both cardioselective as well as 3rd generation beta blockers. As per my knowledge, this hypothesis is still to be tested in clinical trials and is a potential area of research.
Reference: http://heart.bmj.com/cgi/content/abstract/79/1/86
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