Comparative Study of Various Clinical Prediction Scores and D-Dimer in Ruling out Pulmonary Embolism: A Single-Center Prospective Observational Study

A BSTRACT Background: Pulmonary embolism (PE) is one of the greatest diagnostic challenges in emergency medicine, and clinical probability assessment is a fundamental step in its diagnosis. Materials and Methods: All consecutive patients with suspicion of PE were enrolled in the study over a 1-year period. The diagnosis of PE was confirmed by multidetector computed tomography (MDCT) angiography. Patients underwent detailed clinical history, examination, chest X-ray, D-dimer testing, and echocardiography. Well’s and Revised Geneva scores were calculated for all patients. The sensitivity, specificity, predictive value positive, predictive value negative, positive and negative likelihood ratios were calculated for these prediction scores using CT results as the gold standard. Results: On MDCT pulmonary angiography, 64 patients (59.8%) were found to have PE, of which 36 (56.2%) were men, and 28 (43.8%) were women. Well’s Score >4, i.e., PE likely was documented in 59.4% of patients, and Revised Geneva Score ≥11, i.e., high probability of PE was documented in 21.9% of patients. The most sensitive parameter for the diagnosis of PE was the Revised Geneva Score (>4 score) (sensitivity 100%), whereas the Revised Geneva Score ≥11 was the most specific (93% specificity) parameter, followed by the combination of positive D-dimer test and Well’s Score >4 (79.1%). The diagnostic accuracy of Well’s Score >4 (64.5%) was higher than that of the Revised Geneva Score ≥11 (50.5%). Conclusion: Positive D-dimer has the best diagnostic accuracy for the diagnosis of PE. Well’s score has better diagnostic accuracy than the revised Geneva score, especially when combined with positive D-dimer.