Ultrasound lung comets for the differential diagnosis of acute cardiogenic dyspnoea: a comparison with natriuretic peptides.

Acute dyspnoea as a presenting symptom is a frequent diagnostic challenge for physicians. The main differential diagnosis is between dyspnoea of cardiac and non-cardiac origin. Natriuretic peptides have been shown to be useful in this setting. Ultrasound lung comets (ULCs) are a simple, echographic method which can be used to assess pulmonary congestion. To evaluate the accuracy of ULCs for predicting dyspnoea of cardiac origin compared to natriuretic peptides. We evaluated 149 patients admitted with acute dyspnoea. Chest sonography and NT-proBNP assessments were performed a maximum of 4 h apart and independently analyzed. ULCs were evaluated via cardiac probes placed on the anterior and lateral chest. Two independent physicians, blinded to ULCs and NT-proBNP findings, reviewed all the medical records to establish the aetiologic diagnosis of dyspnoea. Cardiogenic dyspnoea was confirmed in 122 patients and ruled-out in 27 patients. The number of ULCs was significantly correlated to NT-proBNP values (r=.69, p<.0001). Receiver operating characteristic analysis, showed an area under the curve of .893 for ULCs and .978 (p=.001) for NT-proBNP, in predicting the cardiac origin of dyspnoea. In patients admitted with acute dyspnoea, pulmonary congestion, sonographically imaged as ULCs, is significantly correlated to NT-proBNP values. The accuracy of ULCs in predicting the cardiac origin of dyspnoea is high.