Beta blockers, or beta-adrenergic blocking agents, can be used to treat many of the detrimental symptoms of heart failure. The disease, which is a clinical condition that presents with the heart’s inability to pump adequate amounts of oxygenated blood, is treated routinely with beta-blocking medication. Beta blockers address the symptoms of heart failure caused by an overabundance of a class of hormones, called the catecholamines. In addition, beta blockers can treat other symptoms that may be present, including high blood pressure, chest pain, and heart arrhythmia. Using beta blockers in heart failure has proven to reduce the need for hospitalization, slow the progression of the disease, and reduce the overall risk of fatality.
The use of beta blockers in heart failure is primarily associated with the medication’s effect on heart rate. The medication, by way of the sympathetic nervous system, decreases the patient’s heart rate, preventing the heart from having to work harder because of the condition. This effect was not considered desirable for heart failure patients when the medication was first studied, however. A lowered heart rate has the risk of worsening heart failure symptoms, but as research continued, beta blockers proved to have benefits that outweighed this risk. The exact etiology of the case of heart failure is of importance when a doctor is deciding whether to use beta blockers. A case that is present because of impaired ventricular filling, in contrast to a case caused by impaired ventricular emptying, seems to respond better to beta blockers in heart failure.
In addition to their sympathetic action on heart muscle, beta blockers in heart failure influence the kidney’s renin/angiotensin system. Beta blocking medications cause the secretion of the hormone, renin, to decrease. As renin decreases, a cascade of events transpires that decrease the heart’s demand for oxygen. The cascade lowers extracellular fluid volume and increases the blood’s ability to hold and carry oxygen to body tissues. Beta blocker treatment can be supplemented, and is supplemented in most cases, with diuretics and angiotensin-converting enzyme (ACE) inhibitors that enhance this effect.
Patients who have significant dyspnea — shortness of breath — while they remain at rest are among those who may not be candidates for treatment with beta blockers. Having severe dyspnea can increase the risks that are associated with beta blocker treatment. Some patients are considered hemodynamically unstable if their blood does not carry oxygen well, even under normal circumstances; these patients may not be good candidates for treatment either.