The C Reactive Protein Albumin Lymphocyte Index Refines Prognostic Prediction after Endovascular Repair of Type B Aortic Dissection

OBJECTIVE: Systemic inflammation is central to aortic wall degradation in type B aortic dissection (TBAD). This multicentre, retrospective cohort study aimed to evaluate the prognostic value of the C reactive protein albumin lymphocyte (CALLY) index, which integrates inflammation, nutrition, and immunity, for predicting aorta related adverse events (ARAEs) after thoracic endovascular aortic repair (TEVAR). METHODS: The study enrolled 547 TBAD patients undergoing TEVAR from three tertiary hospitals. Predictive performance of the CALLY index for short (30 days) and long term (120 months) ARAEs was assessed against established indices using receiver operating characteristic curves (AUC) with Delong's test. Incremental value over a clinical baseline model (age, sex, hypertension) was quantified via net re-classification improvement and integrated discrimination improvement. Clinical utility was evaluated by decision curve analysis (DCA). Multivariable Cox regression identified independent predictors of ARAEs. RESULTS: The CALLY index demonstrated superior discriminative ability for both short (AUC 0.757, 95% confidence interval [CI] 0.69 - 0.84) and long term (AUC 0.775, 95% CI 0.73 - 0.82) ARAEs, significantly outperforming all other indices (all p < .001). It improved risk re-classification over the baseline model (long term net re-classification improvement 0.402, 95% CI 0.28 - 0.52; p < .001), and DCA confirmed clinical net benefit. A low pre-operative CALLY index was the strongest independent predictor of short (adjusted hazard ratio [aHR] 5.390, 95% CI 2.34 - 12.41; p < .001) and long term (aHR 4.102, 95% CI 2.85 - 5.90; p < .001) ARAEs. Post-operatively, the CALLY index increased significantly (p = .027), with greater increases in patients without subsequent ARAEs (p < .001). A low CALLY index was associated with lower complete false lumen thrombosis rates (60.6% vs. 73.8%; p < .001). CONCLUSION: The pre-operative CALLY index is a valuable, integrative biomarker that refines risk stratification and predicts impaired aortic remodelling post-TEVAR. It may inform personalised post-operative management strategies in TBAD patients.