Correlation of D-dimer level with the radiological severity indexes of pulmonary embolism on computed tomography pulmonary angiography

Abstract

BACKGROUND: It is known that the main role of D-dimer has been as an exclusionary test in patients with suspected venous thromboembolism. However, the D-dimer is increasingly beginning to find clinical utility as a marker in the evaluation of the extent of the embolic disease. The aim of the study was to determine whether D-dimer levels predict the radiological markers of pulmonary embolism (PE) severity using Mastora score. METHODS: This prospective study involved 69 patients with acute PE proved by computed tomography pulmonary angiography (CTPA). The D-dimer level was noted. A pulmonary artery obstruction index (PAOI; Mastora score) ≥ 21.3% indicated severe obstruction of PE. A right ventricle/left ventricle (RV/LV) ratio >0.9 indicated RV dysfunction. RESULTS: The median D-dimer level and PAOI were 765 µg/L (95% CI: 750-1 205 µg/L) and 16.77% (95% CI: 16.32%-23.06%), respectively. The D-dimer level was positively correlated with PAOI (r = 0.417, P < 0.000 1). PAOI ≥ 21.3% was associated with high D-dimer levels (median, 993 µg/L (95% CI: 856-1 841 µg/L), Z = -2.991, P = 0.003). The D-dimer level was correlated with the RV/LV ratio (r = 0.272, P = 0.024). RV/LV ratios >0.9 were associated with high D-dimer levels (median, 880 µg/L (95% CI: 764-1 360 µg/L), Z = -2.070, P = 0.038). PAOI was positively correlated with the RV/LV ratio (r = 0.390, P = 0.001). After three months, both the PAOI and D-dimer levels decreased (Z = -7.009, P < 0.000 1; Z = -6.976, P < 0.000 1, respectively). CONCLUSION: D-dimer levels are positively correlated with PE burden and right ventricle dysfunction on CTPA, and can help monitor the therapeutic response.