The characteristics of distal tears affect false lumen thrombosis rate after thoracic endovascular aortic repair for acute type B dissection

OBJECTIVES: A low false lumen thrombosis rate (FLTR) is common in patients with type B aortic dissection after they have undergone thoracic endovascular aortic repair, which indicates a poor long-term prognosis. This study aimed to establish a quantitative linear regression model to predict false lumen (FL) thrombosis accurately using morphological parameters. METHODS: In this retrospective study, we included 59 patients diagnosed with acute type B aortic dissection between 2014 and 2017. Morphological parameters were measured. Univariable and multivariable linear regression analyses were performed, and a linear regression model relating FLTR with the number of re-entry tears was proposed. Ten patients were further chosen to validate the linear relationship, and idealized aortic dissection models were adopted for haemodynamic analysis. RESULTS: Only the total area and number of re-entry tears were negatively correlated with FL thrombosis (P < 0.001). Moreover, based on the univariable regression, the number of re-entry tears played a more crucial role in FLTR (R2 = 0.509 vs R2 = 0.298), and the linear relationship model was created as follows: thrombosis rate (%) = -11.25 × distal tear number + 105.24. This model was perfectly matched in 10 patients (concordance correlation coefficient = 0.880, P = 0.947). Moreover, when the total area of re-entry tears was constant, the net blood flow increased rapidly with an increase in the tear count. CONCLUSIONS: The number of re-entry tears could be a crucial related factor of FL thrombosis; the larger the number of re-entry tears is, the lower the possibility of thrombosis is.