Clinical implications of pleural effusion in patients with acute type B aortic dissection.

Background: Pleural effusion may complicate acute Stanford type B aortic dissection (ABAD).

Aims: To identify the relationships between the quantity and side of the pleural effusion, biomarkers and outcomes in patients with ABAD.

Methods: We undertook a retrospective review of 105 patients with ABAD. Their demographics, the data on admission and during hospital stay, the volume of pleural effusion calculated from the area on computed tomography images and clinical outcomes were analysed.

Results: The median estimated peak volume (median 6.7 days after onset) was 129 ml (63-192, range 26-514 ml) on the left and 11 ml (6-43, range 2-300 ml) on the right. On univariate analysis, the volume of bilateral effusions was associated with anaemia, hypoalbuminaemia and inflammatory markers, whereas the volume of left-sided effusions was associated with older age, low diastolic blood pressure and maximum aortic diameter. Multivariate analysis revealed that hypoalbuminaemia was independently associated with bilateral effusion volume ( P<0.001), while maximum aortic diameter was associated with left-sided effusion volume ( P=0.019). A greater volume of bilateral plural effusion was associated with longer intensive care unit stay.

Conclusions: Larger bilateral pleural effusions in patients with ABAD were associated with hypoalbuminaemia and potentially with anaemia and inflammation, and may increase the length of intensive care unit stay. Left-sided effusion volume appears to be influenced by the nature of the aortic dilatation. Multiple mechanisms may underpin the development of pleural effusion in ABAD, and are likely to influence clinical outcomes.