Background: Diagnosing Pulmonary Thromboembolism (PE) remains difficult due to its non-specific symptoms and signs. There is currently no single, reliable, non-invasive diagnostic test sufficiently sensitive to consistently diagnose suspected PE. The aim of this study was to determine the sensitivity and specificity of multi-organ ultrasonography combined with clinical scores and elevated D-dimer levels for the diagnosis of non-massive PE.
Materials and Methods: Between November 2015 and July 2016, a total of 92 consecutive patients with a moderate to high clinical suspicion of PE were evaluated in the emergency setting of our hospital. Those who met the inclusion criteria were enrolled into the study. The demographic, clinical and radiological features of the included patients and their laboratory findings were recorded. At the first assessment the Wells clinical scores were calculated and plasma D-dimer levels were measured using a quantitative enzyme-linked immunosorbent assay. Patients included in the study underwent Thoracic Ultrasonography (TUS), duplex sonography of their lower extremity veins, echocardiography and multislice Computerized Tomography Pulmonary Angiography (CTPA) within 24 h. All statistical analyses were carried out using the SPSS software (version: 16.0; SPSS Inc., Chicago, IL, USA). The chi-squared test was performed to compare categorical variables between groups, while ttests were used for normally distributed continuous variables. Analyses of sensitivity, specificity, Negative Predictive Value (NPV) and Positive Predictive Value (PPV) were conducted using cross-tables in SPSS. A p-value<0.05 was considered significant.
Results: Of the 92 patients, 74 met the inclusion criteria and were included in the study. The mean age of the patients was 55.2 ± 17.4 y old, and 56.8% were male. While PE was diagnosed in 49 (66.2%) patients according to the results of the multislice CTPA (the reference test), PE was not detected in 25 (33.8%) patients. When multi-organ ultrasonography was consistent with PE and evaluated together with increased Ddimer levels, the sensitivity for identifying PE was found to be 89.8%, specificity was 88%, PPV was 93.6% and NPV was 81.5%.
Conclusion: Multi-organ ultrasonography is a more effective and reliable test for diagnosing PE than single-organ ultrasonography. It has a high sensitivity and specificity, especially in the emergency setting. This approach may facilitate immediate treatment decisions when CTPA is not available or feasible.