The Plasma Level of B-Type Natriuretic Peptide is a Useful Predictor of Cardiac Events for Out-Clinic Patients with Asymptomatic Heart Failure

Abstract

Purpose: The circulating level of B-type Natriuretic Peptide (BNP) is recognized as a biomarker of ventricular dysfunction. In the field of primary prevention, BNP is a useful predictor of cardiac death, heart failure, cerebral infarction, and atrial fibrillation. On the other hand, the predictive value of BNP has not been fully elucidated in patients with coronary artery disease and/or those who are prone to atherosclerosis. Methods: We analyzed 679 patients (average age, 65.3 years; 29.2% women) with asymptomatic heart failure (ACC/AHA stage A to B) undergoing total risk management for cardiovascular disease prevention in the Kitasato Registry for Cardiovascular Disease Prevention. The mean follow-up period was 8.4 years (range, 73–3686 days) for all study patients. Results: Among all patients, 54.0% had coronary artery disease, 54.2% had hypertension, 55.7% had dyslipidemia, 31.2% had diabetes mellitus, and 15.5% had atrial fibrillation. The baseline level of plasma BNP was 47.5 (63.8) [mean (SD)] pg/mL. The plasma BNP level correlated with age and the serum creatinine level. The presence of coronary artery disease or atrial fibrillation significantly affected the plasma level of BNP (P <0.05, P <0.01; respectively). Plasma BNP levels were significantly higher in the event group than in the event-free group [80.4 (123.3) vs. 43.4 (50.8) pg/mL, P <0.0001]. Of all patients, 59 experienced cardiac events and 10 died during the study period. In the multivariate analysis, plasma BNP level, age, and diabetes mellitus were identified as predictive factors. The Cox proportional hazards model showed that the plasma BNP level was an independent predictor of cardiac death. The event-free rate was significantly higher in patients with BNP of 40 pg/mL or less than in those with BNP of 40pg/mL or more. Conclusions: In the present long-term follow-up study, we found that the plasma level of BNP of patients who are in a stable condition was a useful prognostic marker. Circulating levels of plasma BNP could be an independent predictor of cardiac events in patients with asymptomatic heart failure.