RESUMEN
INTRODUCTION: The diagnosis of chronic heart failure (CHF) is based on demonstrating the cardiac origin of clinical manifestations. Echocardiography is the method of choice for the detection of left ventricular systolic dysfunction (LVSD). Brain natriuretic peptide (BNP) rises during LVSD. OBJECTIVES: To analyze the plasma concentration of N-terminal brain natriuretic propeptide (NTproBNP) in a general adult population in relation to different spontaneous circumstances and to study its capacity for identifying patients with LVSD.Methods. A cardiological examination was made and plasma NTproBNP levels were measured in a randomized group of 203 people (49-81 years old) from the Community of Valencia. RESULTS: The average NTproBNP concentration was 52.2 98.2 pmol/l. NTproBNP levels varied with age, gender and functional stage (NYHA). The highest NTproBNP values were observed in people who had previously suffered from acute pulmonary edema or who had an ejection fraction (EF) of less than 40%. There was also a significant elevation in patients with nocturnal dyspnea, orthopnea, atrial fibrillation, EF < or = 50%, angina, and ankle edema. The best concentration of NTproBNP for differentiating EF < or = 50% was 37.7 pmol/l, with 92% sensitivity and 68% specificity. CONCLUSIONS: The elevation of NTproBNP concentration indicates the cardiac origin of clinical manifestations and serves to select patients for echocardiographic examination. Low NTproBNP concentrations help to rule out LVSD.