Incremental predictive power of B-type natriuretic peptide and tissue Doppler echocardiography in the prognosis of patients with congestive heart failure.

ABSTRACT

OBJECTIVES: This study was designed to determine how novel indexes of left ventricular (LV) filling pressure-transmitral early diastolic velocity/tissue Doppler mitral annular early diastolic velocity (E/Ea) and B-type natriuretic peptide (BNP)-compare to conventional predictors of outcome in patients with congestive heart failure (CHF). BACKGROUND: It is known that E/Ea can predict LV filling pressure in patients with cardiac disease, including, in contrast to conventional Doppler indexes, in normal ejection fraction. B-type natriuretic peptide has also been correlated to LV filling pressure, but appears to provide more global cardiac information than E/Ea. It is unknown, however, how these novel indexes compare to conventional predictors of CHF patient outcome. METHODS: A total of 116 consecutive patients hospitalized with CHF underwent simultaneous clinical assessment, BNP, and comprehensive echo-Doppler study once ready for discharge. The ability of these variables to determine the primary end point (cardiac death or re-hospitalization for CHF) was determined. RESULTS: Follow-up was complete on 110 of 116 patients at a mean of 527 days after hospital discharge. There were 54 patients (50%) with the primary end point (37 re-hospitalizations for CHF and 17 cardiac deaths). On Cox univariate analysis, E/Ea (chi-square = 13.6, p = 0.0001) and BNP (chi-square = 17.0, p < 0.0001) were significant predictors of the primary end point. In stepwise analysis, BNP >/=250 pg/ml and mitral E/Ea >/=15 had incremental predictive power (chi-square = 23.1, p for increment = 0.02), to which conventional predictors did not add further prognostic information. CONCLUSIONS: In patients admitted to hospital with CHF, pre-discharge BNP and E/Ea are incremental predictors of outcome, to which conventional predictors do not significantly add.