Objectives: To characterize chest radiographic
interpretations in a large population of patients who have received a
diagnosis of acute pulmonary embolism and to estimate the sensitivity
and specificity of chest radiographic abnormalities for right
ventricular hypokinesis that has been diagnosed by
Design: A prospective observational
study at 52 hospitals in seven countries.
total of 2,454 consecutive patients who had received a diagnosis of
acute pulmonary embolism between January 1995 and November 1996.
Results: Chest radiographs were available for 2,322
patients (95%). The most common chest radiographic interpretations
were cardiac enlargement (27%), normal (24%), pleural effusion
(23%), elevated hemidiaphragm (20%), pulmonary artery enlargement
(19%), atelectasis (18%), and parenchymal pulmonary infiltrates
(17%). The results of chest radiographs were abnormal for 509 of 655
patients (78%) who had undergone a major surgical procedure within 2
months of the diagnosis of pulmonary embolism: normal results for chest
radiograph often accompanied pulmonary embolism after genitourinary
procedures (37%), orthopedic surgery (29%), or gynecologic surgery
(28%), whereas they rarely accompanied pulmonary emboli associated
with thoracic procedures (4%). Chest radiographs were interpreted to
show cardiac enlargement for 149 of 309 patients with right ventricular
hypokinesis that was detected by echocardiography (sensitivity, 0.48)
and for 178 of 485 patients without right ventricular hypokinesis
(specificity, 0.63). Chest radiographs were interpreted to show
pulmonary artery enlargement for 118 of 309 patients with right
ventricular hypokinesis (sensitivity, 0.38) and for 117 of 483 patients
without right ventricular hypokinesis (specificity, 0.76).
Conclusions: Cardiomegaly is the most common chest
radiographic abnormality associated with acute pulmonary embolism.
Neither pulmonary artery enlargement nor cardiomegaly appears sensitive
or specific for the echocardiographic finding of right ventricular
hypokinesis, an important predictor of mortality associated with acute