Relationship between false lumen morphology and entry tear in acute type A aortic dissection.

Objectives: This study aimed to investigate the relationship between false lumen morphology and the size, aortic segment and position of the entry tear for acute type A aortic dissection.

Methods: The records of patients who underwent emergency operation for acute type A aortic dissection in our institution between April 2011 and May 2022 were examined. Data regarding size, location and position of the entry tear and preoperative computed tomography findings were reviewed. The relationship of these variables with false lumen morphology was examined and retrospectively compared according to tear size.

Results: Of 243 cases, characteristics of the entry tear, visualized during surgery, were confirmed in 134 cases (age = 70.9 ± 12.6 years, male = 45.5%). Tear sizes at different aortic segments were not significantly different (P = 0.376). Tears posterior to the lesser curvature were significantly smaller than those anterior to the greater curvature (P = 0.004). A thrombosed false lumen was associated with a significantly smaller tear size and position on the posterior to the lesser curvature side in aortic cross-section (all P < 0.001). Multivariate analysis showed that tear size, the presence of re-entry and tear position anterior to the greater curvature were independent predictors of a patent false lumen.

Conclusions: In acute type A aortic dissection, larger tear size, the presence of re-entry and tear position anterior to the greater curvature are risk factors for a patent false lumen. Although the results of this study are valid only for patients in whom intimal tears were detected during aortic surgery, this trend may provide information for pathophysiology of the disease.