ACUTE PULMONARY-EMBOLISM - VALUE OF TRANSTHORACIC AND TRANSESOPHAGEALECHOCARDIOGRAPHY IN COMPARISON WITH HELICAL CT

OBJECTIVE. The goal of this study was to prospectively compare the acc uracy of transthoracic and transesophageal B-mode and Doppler echocard iography with helical CT for detecting acute pulmonary embolism. SUBJE CTS AND METHODS. Thirty-five consecutive patients underwent transthora cic and transesophageal echocardiography and contrast-enhanced helical CT. Echocardiographic examinations were analyzed for indirect criteri a, including increased main pulmonary artery diameter, tricuspid regur gitation, and dilatation of the right ventricular cavity, as well as f or direct thrombus visualization. Sensitivity, specificity, and negati ve and positive predictive values were calculated. RESULTS. Pulmonary embolism was revealed by helical CT in 22 of 35 patients; in 11 of the se 22 cases, central pulmonary embolism was seen. Transthoracic and tr ansesophageal B-mode echocardiography failed to reveal pulmonary embol ism in nine patients, two of whom had central pulmonary embolism. The sensitivity and specificity of the combination of both echocardiograph ic investigations were 59% and 77% respectively (82% and 92% for centr al pulmonary embolism). In three patients, pulmonary embolism was diag nosed by direct clot detection with transesophageal echocardiography. In two patients, only the indirect parameters indicated pulmonary embo lism. Overall indirect echocardiographic parameters were characterized by a low sensitivity that ranged from 50% for tricuspid regurgitation to 21% for main pulmonary artery diameter. CONCLUSION. In comparison with helical CT, transthoracic and transesophageal echocardiography ha d limited accuracy for detecting pulmonary embolism.