Background: B-type natriuretic peptide (BNP) and N-terminal pro-BNP levels are useful in diagnosing acute decompensated heart failure, and can also predict clinical outcomes in patients with chronic heart failure. It has been proposed that adjusting heart failure therapy to reduce BNP plasma levels may improve clinical outcomes. However, the benefit of this approach remains uncertain because many trials have been underpowered to detect the effect on major cardiovascular events. Porapakkham and colleagues performed a meta-analysis of prospective randomized controlled trials that examined BNP-guided therapy versus clinically guided treatment in the outpatient management of heart failure.
The Study: Trials had to have more than 20 patients and have clinically relevant end points (e.g., all-cause mortality, hospitalization) to be included in the meta-analysis. The likelihood of these end points was assessed when standard heart failure treatments (e.g., angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, aldosterone antagonists, beta blockers) were titrated to improve clinical status (e.g., New York Heart Association [NYHA] functional class) versus adjusting treatment to acheive specified BNP or pro-BNP levels, with or without clinical status improvement (e.g., the Systolic Heart Failure Treatment Supported by BNP study had a target BNP level of less than 100 pg per mL [100 ng per L], whereas the Trial of Intensified versus Standard Medical Therapy in Elderly Patients with Congestive Heart Failure used a target N-terminal pro-BNP level of less than 400 pg per mL [400 ng per L] in addition to NYHA functional class II or lower in adults younger than 75 years).
Results: Eight trials with 1,726 patients were analyzed. All participants were 18 to 85 years of age and had NYHA functional class II or greater heart failure with left ventricular ejection fraction less than 50 percent. The mean follow-up duration was 17 months (range: three to 24 months). All-cause mortality was significantly lower among patients in the BNP-guided therapy group compared with those in the standard therapy group (relative risk = 0.76). Subgroup analysis found this effect was even more significant in patients younger than 75 years (relative risk = 0.52), but BNP-guided therapy did not reduce mortality in patients 75 years and older. No significant differences were noted between groups with regard to all-cause hospitalization or hospitalization-free survival.
Conclusion: The authors conclude that BNP-guided therapy can significantly lower all-cause mortality in patients younger than 75 years with chronic heart failure compared with standard therapy. However, all-cause hospitalization and hospitalization-free survival rates remain unaffected.