The effects of ejection fraction on N-terminal ProBNP and BNP levels in patients with acute CHF: analysis from the ProBNP Investigation of Dyspnea in the Emergency Department (PRIDE) study - O'Donoghue, M; Chen, A; Baggish, A L; Anwaruddin, S; Krauser, D G; Tung, R; Januzzi, J L (J Card Fail, 2005)