Prognostic value of Mastora obstruction score in acute pulmonary embolism

To evaluate the clinical significance of Mastora obstruction score in hemodynamically stable patients with acute pulmonary embolism (aPE).

One-hundred-and-six patients with newly diagnosed aPE, confirmed by computed tomography pulmonary angiography (CTPA), were included in the study and prospectively examined. aPE severity was assessed by using Mastora obstruction score. According to the Mastora index, patients were divided into "non-massive" and "massive" groups. The  patients' medical histories and blood laboratory data were collected, and instrumental tests were performed and analyzed.

Eighty-two (77%) of the patients had "non-massive" aPE. Cough (48%), fever (44%), and pleural effusion (48%) occurred significantly more often in the  "non-massive" PE group, while syncope (42%) and right ventricular dysfunction (86%) were more frequent in the  "massive" PE group. The  probability of the  right ventricular dysfunction was significantly higher in the  presence of increased pulmonary artery pressure (Cramer's V = 0.410; p < 0.0001) and respiratory failure (Cramer's V = 0.247; p = 0.032). Increased CRP level was found in the majority of the patients (90%). D-dimer level <500 μg/L (lower than the commonly recommended cut-off level) was found in 5% of cases.

The clinical manifestation depends on the massiveness of aPE. Division of aPE cases into two groups suggests two possible subtypes of aPE: cardiovascular and respiratory. The "non-massive" aPE was associated with respiratory symptoms and an inflammatory response. The  "massive" aPE is associated with an increased D-dimer level and leads to cardiovascular disorders. However, the "massive" aPE may be presented by normal D-dimer concentration level.