Abstract: Objective · To analyze and evaluate the diagnostic value of plasma D-dimer combined with echocardiography and lower extremity vascular ultrasound for pulmonary thromboembolism (PTE). Methods · The clinical data of 140 clinically suspected PTE patients admitted to Department of Respiratory and Critical Care Medicine, Ruijin Hospital between January 2012 and December 2016 were retrospectively analyzed. Based on the results of computed tomographic pulmonary angiography (CTPA), all included patients were divided into CTPA negative group (non-PTE group) and CTPA positive group (PTE group). The univariate and multivariate analyses were used to compare and evaluate the diagnostic and predictive efficacy of plasma D-dimer combined with echocardiography and lower extremity vascular ultrasound for PTE. Results · There was no significant difference in gender, age, smoking, underlying diseases (malignancy, hypertension, coronary heart disease, dyslipidemia, and chronic obstructive pulmonary disease) and surgical history within 30 days between the two groups (All P>0.05). Univariate analysis revealed significant differences in D-dimer (P0.003), pulmonary artery pressure (P0.000), and partial pressure of carbon dioxide (P0.000) between the groups. Multivariate analysis suggested that deep venous thrombosis of the lower extremities, pulmonary hypertension, and elevated D-dimer levels were significantly associated with the incidence of PTE. Further ROC curve analysis suggested that the area under the curve (AUC) of deep venous thrombosis, pulmonary hypertension and D-dimer increase was 0.624, 0.673 and 0.624, respectively. The AUC of combined three factors was 0.837. The sensitivity, specificity, positive predictive value and negative predictive value of the combined diagnosis reached 86.8%, 88.4%, 87.5%, and 84.6%, respectively. Conclusion · D-dimer combined with echocardiography and vascular ultrasound of lower extremity might have diagnostic and predictive value for PTE.

Key words: pulmonary thromboembolism (PTE), D-dimer, pulmonary hypertension, deep vein thrombosis of lower extremity, combined diagnostic value