Page 76 - Biomarkers for risk stratification and guidance in heart failure

Management of chronic heart failure guided by individual NT-proBNP targets.
The report1 and editorial2 in a recent issue of the Journal on N-terminal pro–B-type
natriuretic peptide (NT-proBNP) in the management of patients with heart failure
(HF) led to the conclusion that B-type natriuretic peptide has not fulfilled original expectations, although NT-proBNP provided advanced detection of events and
enhanced medication use. The editorial pointed out that although NT-proBNP did
not improve events, this could partially reflect the need for a larger study, adoption
of individualized NT-proBNP targets, timing of the sampling for the nadir of NT-
proBNP, and threshold percentage rise in NT-proBNP for up-titrating therapy. They
also recommended consideration of the patients’ age, other factors influencing 3 BNP, systolic dysfunction, and use of individual patient data in meta-analyses.
Trials of HF should include, along with the parameters under study, a minimum of information currently used in the management of patients. The cornerstone of the assessment of a patient with HF is the history and physical examination (pulmonary rales, elevated mean jugular venous pressure, and peripheral edema \[PERED\]), although these conditions are insensitive and do not correlate with hemodynamics.3 PERED is often undetected until the patient has accumulated approximately 10 l of fluid.4 Body weight (BW) is used in all clinical encounters with patients with HF, and it should be a study variable in HF trials. Did the researchers have BW measurements of their patients? If so, what was the correlation between the BW and NT-proBNP percentage perturbations? The quoted “negative” study3 included a “positive” correlation (r = 0.82) of proportional pulse pressure (systolic blood pressure \[SBP\] diastolic blood pressure \[DBP\]/SBP) with cardiac index. The mean SBP and DBP in Table 1 (1) were not statistically significant, although individual patient values are needed to calculate proportional pulse pressure.
*John E. Madias, MD
*Department of Medicine Division of Cardiology Elmhurst Hospital Center 79-01 Broadway, Elmhurst, New York 11373
REFERENCES
1. Eurlings LW, van Pol PE, Kok WE, et al. Management of chronic heart failure guided by individual N-terminal pro–B-type natriuretic peptide targets: results of the PRIMA (Can Pro-Brain-Natriuretic Peptide Guided Therapy of Chronic Heart Failure Improve Heart Failure Morbidity and Mortality?) study. J Am Coll Cardiol 2010;56:2090 –100.
2. Troughton RW, Frampton CM, Nicholls MG. Biomarker-guided treatment of heart failure: still waiting for a definitive answer. J Am Coll Cardiol 2010;56:2101– 4.
3. Stevenson LW, Perloff JK. The limited reliability of physical signs for estimating hemodynamics in chronic heart failure. JAMA 1989;261:884–8.
4. Fauci AS, Braunwald E, Kasper DL, et al., editors. Harrison’s Principles of Internal Medicine. 17th edition. New York, NY: McGraw-Hill Medical Publishing Division, 2008:231– 6.
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