Transesophageal echocardiography for the diagnosis of pulmonary embolism with acute cor pulmonale: a comparison with radiological procedures

Objective: The goal of the study was to assess prospectively the value of transesophageal echocardiography (TEE) for the diagnosis of massive pulmonary embolism complicated by acute cor pulmonale. Design: A prospective study conducted on 44 consecutive patients. Setting: A general intensive care unit (ICU) of a university hospital, Patients and methods: Between May 95 and October 96, 44 consecutive patients with clinically suspected acute pulmonary embolism underwent transthoracic echocardiography (TTE), completed by TEE when acute cor pulmonale was present (30 patients). The results of the echocardiographic studies were compared with radiological investigations by helical CT or contrast angiography. Results: The high sensitivity and specificity of the presence of acute cor pulmonale on TTE for the diagnosis of pulmonary embolism was confirmed. Nineteen patients only underwent TEE. The sensitivity and the specificity of TEE in detecting a proximal pulmonary embolism were 84 % and 84 %, respectively. Its main limitation concerned the left pulmonary artery, in which only one thrombus was visualized by TEE whereas six were present on helical CT, and lobar pulmonary arteries which could not be visualized with TEE. Thus, the overall sensitivity of TEE for the detection of pulmonary embolism with acute cor pulmonale was only 58 %. Conclusion: In comparison with radiological procedures, TEE had limited accuracy for detecting pulmonary embolism with acute cor pulmonale, When the pulmonary embolism was located in the main or right pulmonary artery, TEE could clarify the diagnosis within a few minutes without further invasive diagnostic procedures. However, a negative TEE did not exclude left proximal or lobar pulmonary embolism.