The aim of this study was to investigate the clinical utility of echocardiography in the diagnosis of pulmonary embolism (PE). For this, we enrolled 162 patients with suspected PE in a prospective study. We evaluated the sensitivity and specificity of right ventricular dilatation, the Doppler evidence of pulmonary hypertension, and their possible associations. We also calculated the number of lung-scan angiography procedures avoided and the number of patients unnecessarily treated when echocardiography was included in the diagnostic work-up. The sensitivity and specificity of echocardiography ranged between 29 and 52% and between 96% and 87%, respectively. Adding echocardiography to the diagnostic strategy for PE would avoid about 12 to 28% of lung-scan angiography procedures, but would cause inappropriate treatment of 4 to 14% of all treated patients. The clinical utility of echocardiography in the diagnosis of PE is limited. The reduction in the number of standard diagnostic procedures obtained through its use would be counterbalanced by an excess of patients inappropriately treated.