Beta Blockers That are Used in Managing Heart Failure Heart failure occurs when the heart is not able to pump or fill with blood to reach the body needs, leading to decrease in pumping action and cardiac output. The body will sense the hypo-perfusion of vital organs then activate the compensatory mechanisms. First compensatory mechanism is cardiac compensation by increasing the heart rate, contractility, or myocardial hypertrophy and remodeling. Additionally, systemic compensation by increasing the blood volume via sodium water retention or redistribution of blood to vital organs. Moreover, neurohormonal compensation mechanism in which the body activate sympathetic nervous system, renin angiotensin aldosterone system, as well as release …show more content…
In heart failure, beta-1 receptor is down regulated, while beta-2 receptor is uncoupled from post-receptor event. The benefit of beta blockers depends on blocking beta-1 receptor. Beta-blockers in general antagonize the effect of catecholamines, resulting in negative chronotropic effect and negative inotropic effect. Possible mechanisms for beta blockers to improve survival include: anti-arrhythmic and anti-ischemic action, attenuation of catecholamine toxicity, as well as reduced cardiac remodeling. Metoprolol and bisoprolol are selective beta-1 blockers, while carvedilol is a non-selective beta blocker with additional alpha-1 blocking and antioxidant properties. There are several clinical trials show that beta blocker, such as metoprolol, bisoprolol, carvedilol, and nebivolol, are used to treat heart …show more content…
In addition to reducing the contractility and heart rate by blocking beta-1 receptors, nebivolol induces phosphorylation of the endothelial enzyme endothelial NO synthase to produce NO, resulting in vasodilatory effect. Clinical trials have compared nebivolol with carvedilol in the treatment of patients with heart failure. Nebivolol improved the left ventricular ejection fraction, left ventricular volumes, and exercise capacity. Additionally, the Study of the Effects of Nebivolol Intervention on Outcomes and Re-hospitalization in Seniors with Heart Failure, or SENIORS, conclude that nebivolol reduced the number of deaths when compared with placebo. There are no large clinical trials have compared nebivolol with currently recommended beta blockers in hearts failure