Chronic heart failure affects a sig...

Chronic heart failure affects a significant number of parts in the United States. newly come studies have demonstrated that sympathetic activation is an important composing of the pathophysiology in the progression of disease in patients with left ventricular systolic dysfunction. Serum catecholamine plains are elevated in patients with systolic dysfunction and cause a down-regulation of b1-adrenoceptors. Beta blocker antagonize these receptors and are used in the treatment of left ventricular systolic dysfunction because they have been shown to model myocardial mass, normalize ventricular shape, and improve left ventricular systolic function, functional status, and mortality. Standard treatment in patients with chronic pulmonary disease is inhaled [beta.sub.2]-agonists. These agents can have the opposite result of beta blockers on the heart. Au and associates assessed a assign places to of patients to see if the use of [beta.sub.2]-agonists had any impact onward hospitalizations and mortality in patients with left ventricular dysfunction.

The thought was of a cohort of patients who were seen in a Veterans Affairs health care method and had a cardiac ejection fraction of les than 45 percent established by dint of cardiac imaging examination. All patients were followed for at least undivided year after they entered the contemplation The outcomes evaluated were the first hospitalization with the primary diagnosis of chronic heart failure or death from any cause. Patients registered in the study had their pharmacy records reviewed for the filling of prescriptions for [beta.sub.2]-agonists from 90 days before to 15 days after inquiry enrollment. Use of both canisters and nebulized [beta.sub.2]-agonists was recorded.

There were 1529 patients enlisted in the study. The relative risk for hospitalization for chronic heart failure was 14 in those who used individual canister of [beta.sub.2]-agonist, 1.7 in those who used brace canisters, and 2.1 in those who used three canisters compared with those who did not use [beta.sub.2]-agonists. The relative risk of death in these patients followed a similar pattern. In those who received [beta.sub.2]-agonist from nebulizer, the relative risk for heart failure was 19 and the relative risk for death was 32 Adding in multiple comorbidity factors and cardiac medication use did not change these relative risks.

The authors decide that patients with left ventricular systolic dysfunction who use an inhaled [beta.sub.2]-agonist have an increase in the risk for heart failure exacerbation and all-cause mortality. They add that patients with known left ventricular systolic dysfunction who are receiving high dosages of a [beta.sub.2]-agonist should assess the potential cause of this increase in use and consider that it may be a worsening of heart failure symptoms and not an exacerbation of pulmonary disease.

Au DH et al. Risk of mortality and heart failure exacerbations associated with inhaled b-adrenoceptor agonists among patients with known left ventricular systolic dysfunction. Chest June 2003;123:1964-9

COPYRIGHT 2004 American Academy of Family Physicians

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