Risk stratification in chronic heart failure: independent and incremental prognostic value of echocardiography and brain natriuretic peptide and its N-terminal fragment.

BACKGROUND: It was the aim of this study to compare the prognostic impact of echocardiography and brain natriuretic peptide and its N-terminal fragment (NT-proBNP) in patients with chronic heart failure (CHF).

METHODS: In all, 73 patients with CHF underwent conventional 2-dimensional/Doppler echocardiography and Doppler tissue analysis of systolic, early and late diastolic mitral annular velocities. The mitral filling pattern was classified as restrictive or nonrestrictive. NT-proBNP measurements were carried out on a bench-top analyzer. A cardiac event (rehospitalization caused by worsening CHF, cardiac death, urgent cardiac transplantation) was defined as combined study end point.

RESULTS: During follow-up of 226 +/- 169 days, 27 patients had an event (rehospitalization because of CHF, n = 18; cardiac death, n = 7; urgent transplantation, n = 2). On multivariate Cox regression analysis, a restrictive filling pattern, NT-proBNP, the ratio of peak early diastolic mitral flow to mitral annular E' velocity were independent prognostic predictors. A risk stratification model based on the 3 strongest independent predictors separated groups into those with good, intermediate, and poor outcome (event-free survival of 78%, 46%, and 0%, respectively).

CONCLUSIONS: In patients with CHF, Doppler echocardiography, Doppler tissue imaging, and NT-proBNP provide independent and incremental prognostic information. A combined use of echocardiography and NT-proBNP may help to improve risk stratification in this patient population.