Validity of using serum D-dimer titer in prefatory to computed Tomography pulmonary angiography scans in the early identification of pulmonary embolism amid emergency room patients: a single-center retrospective observational study

Abstract

Background and aim Pulmonary embolism emerges when a thrombus forms in the veins or right heart and travels to the pulmonary arteries. The study aims to ascertain the robustness of D-dimer testing for PE compared with CTPA and identify the threshold values to support its use. Patients and methods The positivity threshold for D-dimer was above 250 ng/ml. CTPA was performed after performing blood sampling. Patients were managed in the ICU with anticoagulants by parenteral use. The most commonly used items were heparin, either unfractionated (UFH) or low-molecular-weight heparin (LMWH). Results Twenty-four patients of the total number of cases were positive for CTPA, while four patients were negative for PE by CTPA. Embolism was detected in the anterior, posterior, medial, and lateral basal segmental branches of the right lung, the lateral, posterior, and anterior basal segmental branches of the left lung, and the posterior segmental branch of the left lung. The D-dimer test and CTPA both provided similarly accurate PE diagnoses with no significant differences between them. There were 28 patients in total, three of those patients had D-dimer levels below the cutoff value of 250 ng/ml, whereas the remaining 25 had D-dimer levels over the diagnostic threshold. Those with a positive CTPA diagnosis of PE had greater levels of D dimers than those with a negative CTPA diagnosis of PE. Conclusion D-dimer levels can help in guiding the option of CTPA and the initiation of treatment for patients with suspected PE.