OBJECTIVES: Rapid evaporative ionization mass spectrometry (REIMS) can discriminate
aneurysmal from normal aortic tissue. Our objective in this work was to probe the
integrity of acute dissection tissue using biomechanical, biochemical and histological
techniques and demonstrate that REIMS can be used to discriminate identified differences.METHODS:
Human aortic tissue was obtained from patients undergoing surgery for acute aortic
dissection. Biomechanical, biochemical and histological assessment was carried out
to probe mechanical properties and elastin, collagen and glycosaminoglycan composition
of the tissue. Monopolar electrocautery was applied to samples and surgical aerosol
aspirated and analysed by REIMS to produce mass spectral data.RESULTS: Tissue was
obtained from 10 patients giving rise to 26 tissue pieces: 10 false lumen (FL), 10
dissection flap and 6 true lumen samples. Models generated from biomechanical and
biochemical data showed that FL tissue was distinct from true lumen and dissection
flap tissue. REIMS identified the same pattern being able to classify tissue types
with 72.4% accuracy and 69.3% precision. Further analysis of REIMS data for FL tissue
suggested patients formed 3 distinct clusters. Histological and biochemical assessment
revealed patterns of extracellular matrix degradation within the clusters that are
associated with altered tissue integrity identified using biomechanical testing.CONCLUSIONS:
Structural integrity of the FL in acute Type A dissection could dictate future clinical
distal disease progression. REIMS can detect differences in tissue integrity, supporting
its development as a point-of-care test to guide surgical intraoperative decision-making.
