N-terminal protype-B natriuretic peptide and Doppler diastolic variables are incremental for risk stratification of patients with NYHA class I–II systolic heart failure

Abstract 

Background

In systolic heart failure (HF), preventing the development of severe symptoms, before patients are in advanced NYHA functional classes, is a worthwhile target of therapy. Early recognition of left ventricular (LV) diastolic dysfunction and neuroendocrine activation may have an important impact on patient's outcome.

Aim

To investigate whether N-terminal proBNP (NT-proBNP) and mitral flow and tissue Doppler (TD) diastolic parameters are incremental for risk stratification of systolic HF patients in NYHA class I and II.

Methods

The study consisted of 232 consecutive outpatients with systolic HF (ejection fraction [EF] ≤45%) in NYHA class I to II. They had a full Doppler two-dimensional-echocardiographic study, including pulsed-Doppler mitral E wave deceleration time (EDT) and TD early septal annular velocity (E′). Plasma NT-proBNP was assessed at the time of the echocardiogram.

Results

During a median follow-up of 31 months, there were 65 events (25 deaths and 40 HF-related hospitalizations). Multivariate analysis showed that N-terminal proBNP >544 pg/ml (hazards ratio [HR]: 2.66; p=0.012), EF <37% (HR: 2.45; p=0.006), E ≤8 cm/s (HR: 1.84; p=0.045) and EDT <150 ms (HR: 1.78; p=0.026) significantly correlated with events. On forward stepwise analysis, EDT (p<0.0001) and E′ (p<0.0001) provided an incremental contribution to the outcome prediction above and beyond conventional risk markers, that was further increased by the addition of NT-proBNP (p<0.0001).

Conclusion

In patients with systolic HF in NYHA functional class I and II, N-terminal proBNP and LV mitral flow and TD variables of diastolic dysfunction had a strong predictive power for the combined end point of all-cause mortality and HF-related hospitalizations.

Keywords: Echocardiography, Heart failure, Diastolic dysfunction, Natriuretic peptides