Accuracy of N-terminal pro-brain natriuretic peptide in the identification of left ventricular dysfunction in high-risk asymptomatic patients.

OBJECTIVE: The role of natriuretic peptides in the screening of left ventricular dysfunction is still unclear. The aim of this study was to assess the usefulness of N-terminal pro-brain natriuretic peptide (NT-proBNP) measurement in asymptomatic patients at high risk of developing left ventricular dysfunction.

METHODS: One hundred and thirty-four consecutive ambulatory patients (mean age 56.1 +/- 7 years) were studied and selected on the basis of a history of hypertension of at least 5 years. Systolic dysfunction was defined as an ejection fraction of 45% or less. Statistical analysis was performed by both parametric and nonparametric approaches. Diagnostic accuracy was evaluated by receiver operating characteristic analysis.

RESULTS: Echocardiography showed normal left ventricular function in 40 patients, diastolic dysfunction in 80 patients and systolic dysfunction in 14 patients. NT-proBNP levels were significantly higher in patients with systolic dysfunction (356.1 +/- 294.8 vs. 85.2 +/- 85.8 pg/ml; P < 0.05). Receiver operating characteristic analysis showed a high value of the area under the curve (0.89) for the detection of systolic dysfunction with a sensitivity of 83% and a specificity of 80% for a cut-off value of 114 pg/ml and with a negative predictive value of 0.98.

CONCLUSION: In asymptomatic patients at high risk for heart failure because of a history of hypertension, the measurement of NT-proBNP levels may represent a useful screening test for left ventricular systolic dysfunction. Therefore, more expensive examinations, such as echocardiography, may be restricted only to patients with higher NT-proBNP levels.