Systemic Inflammatory–Nutritional Status and Coronary Collateral Development in Chronic Total Occlusion: The Role of the CALLY Index

Background:In patients with chronic total occlusion, collateral development varies despite similar angiographic disease burden. The C-reactive protein–albumin–lymphocyte (CALLY) index may reflect systemic inflammatory, nutritional, and immune status, but its association with collateral development in chronic total occlusion (CTO) is not well defined.Methods:We retrospectively evaluated 306 consecutive patients diagnosed with CTO on coronary angiography at a single center between January 2023 and December 2025. Angiographic collateralization was stratified via the Rentrop criteria, where categories 0–1 represented suboptimal vascular recruitment, whereas classes 2–3 denoted a well-developed collateral network. Baseline clinical features, laboratory measurements, and angiographic findings were analyzed according to collateral status. Logistic regression models were used to test the independent relationship between the CALLY index and good collateral development, while ROC analysis assessed its discriminatory performance.Results:Patients with poor collateral development showed a more pronounced inflammatory profile, accompanied by lower albumin levels, lymphocyte counts, and CALLY index values. The median CALLY index was lower among patients with poor collateralization than among those with good collateralization [2.70 (1.30–7.33) vs. 4.56 (2.42–9.27), p