Doppler echocardiography was more accurate than B-type natriuretic peptide assay for detecting CHF in acute dyspnea.

D e s c r i p t i o n o f t e s t s a n d d i a g n o s t i c s t a n d a r d Blood for BNP levels was taken using the Triage BNP test (Biosite Diagnostics, San Diego, CA, USA), a point-of-care method based on fluorescence immunoassay. The BNP measurements were done on frozen plasma approximately 1 to 2 months after blood collection. Doppler echocardiography was done within 60 minutes of enrollment using a Hewlett-Packard Sonos 1500 (Andover, MA, USA) machine with a 2.5MHz probe and included 2-dimensional and M-mode examination, pulsed Doppler analysis of mitral inflow, and continuous Doppler analysis of tricuspid regurgitation. 2 cardiologists and 1 pneumonologist, blinded to BNP assay and Doppler results, collaborated to determine the final diagnosis of CHF based on the Framingham criteria with corroborative information from other cardiac and pulmonary function tests.