Value of platelet indices in prediction of pulmonary embolism

Abstract

Objectives To assess the platelet (PLT) indices, such as mean platelet volume (MPV), plateletcrit (PCT), and platelet distribution width (PDW), in pulmonary embolism (PE) prediction. Background PE is the third most frequent cardiovascular disease worldwide. The changes in PLT indices (MPV, PDW, and PCT) are gold standard markers for the pathogenesis in different cardiovascular diseases. Patients and methods A total of 100 patients with venous thromboembolism and 50 controls were recruited. Overall, 46 patients presented with first episode of deep venous thrombosis (DVT) without PE (group I) and 54 patients with PE (group II). Results MPV was significantly higher in patients with PE (10.72 ± 2.05 fl) than patients with DVT (9.25 ± 1.31 fl) (P = 0.02). Similarly, PDW was significantly higher in patients with PE (24.78 ± 6.76 fl) than patients with DVT (22.39 ± 4.33 fl), with P value of 0.04. The cutoff values of MPV and PDW for prediction of PE at presentation were 10 and 17.5 fl, respectively, with sensitivities of 77 and 83%, respectively, and specificities of 87 and 80%, respectively. PCT was significantly higher in the PE (0.25 ± 0.09 ng/ml) group and DVT (0.26 ± 0.07 ng/ml) group compared with the control (0.22 ± 0.04 ng/ml) group. PLT count was significantly lower in the PE group (229.39 ± 67.98 × 103/μl) than DVT (249.85 ± 54.7 × 103/μl) and control (279.13 ± 61.83 × 103/μl) groups. White blood cell were significantly higher in patients with PE (9.36 ± 3.67 × 109/l) than DVT (8.01 ± 2.53 × 109/l) and control (8 ± 2.37 × 109/l) groups. The highest values of MPV, PDW, right ventricular dimensions, pulmonary pressure, and cardiac troponin I level were significantly correlated to the severity of PE. MPV and PDW were directly related to thrombus size in Doppler ultrasonography finding in patients with DVT and to the level of obstruction of pulmonary vessels in computed tomography pulmonary angiogram for patients with PE. Conclusion The current study suggested that serial measurements of MPV, PDW, and PLT count are reliable markers for predicting the occurrence of acute PE in patients with first episode of acute proximal DVT.