Evaluation of perivascular fat density and residual false lumen formation following TEVAR in Stanford type B aortic dissection.

OBJECTIVE

This study aims to investigate the role of perivascular adipose tissue (PVAT) attenuation in predicting residual false lumen formation following thoracic endovascular aortic repair (TEVAR) in patients with Stanford Type B aortic dissection (TBAD). The focus is on the association between PVAT attenuation (HUand HU) and postoperative outcomes, particularly the development of residual false lumen.

METHODS

A retrospective analysis was conducted on 132 patients who underwent TEVAR for TBAD at Fujian Provincial Hospital between 2016 and 2024. Patients were classified into two groups based on postoperative imaging findings: those with residual false lumen and those with completely closed false lumen. Data collected included demographic, biochemical, and imaging parameters. PVAT was assessed using computed tomography angiography (CTA), with the TotalSegmenter deep learning model used for automatic segmentation. Two indicators-Hounsfield unit difference (HU) and Hounsfield unit ratio (HU)-were calculated.

RESULTS

Patients with residual false lumen showed significantly higher HU (8.75 ± 3.29 vs. 5.16 ± 2.84,  < 0.001) and lower HU (0.73 ± 0.13 vs. 0.85 ± 0.11,  < 0.001) compared to those with closed false lumen. Multivariate logistic regression identified HU and HU as independent predictors of residual false lumen formation after TEVAR. ROC curve analysis revealed optimal cut-off values for predicting residual false lumen: HU > 7.170 (sensitivity 0.895, specificity 0.762) and HU ≤ 0.790 (sensitivity 0.947, specificity 0.667).

CONCLUSIONS

PVAT attenuation, reflected by HU and HU, serves as a significant, non-invasive imaging biomarker for predicting residual false lumen formation after TEVAR in TBAD patients. These findings suggest that preoperative evaluation of PVAT characteristics can help identify high-risk patients and guide postoperative management strategies. Further prospective studies are needed to validate these findings and explore the potential of PVAT modulation in improving long-term outcomes following TEVAR.