Relationship between Systemic Immune-Inflammation Index and Coronary Collateral Circulation in Patients with Chronic Total Occlusion

Abstract Background Inflammation plays a key role in the initiation and progression of coronary artery disease (CAD). The systemic immune-inflammation index (SII) is a novel inflammatory parameter that has been shown to be associated with CAD. Objective This study aimed to investigate the relationship between SII and coronary collateral circulation (CCC) in patients with stable CAD and chronic total occlusion (CTO). Methods The patients were divided into two groups, with poor CCC and good CCC, according to the Rentrop Classification. Ninety-four patients had poor CCC, and 81 patients had good CCC. Inflammation parameters were calculated from the laboratory results. The statistical significance level applied was 0.05. Results High SII level (OR: 1.003, 95% CI: 1.001-1.004, p<0,001), absence of CTO in RCA (OR: 0.204, 95% CI: 0.096-0.436, p<0,001) and low Gensini score (OR: 0.980, 95% CI: 0.962-0.998, p=0,028) were significantly associated with poor CCC. The cutoff value of SII was 679.96 for the highest predictive power of poor CCC, with a sensitivity of 74.5% and specificity of 43.2%. Mortality rates were similar between the two groups during a mean follow-up of 21.5±10.8 months (p=0.107). Conclusions High SII level, the absence of CTO in the right coronary artery, and low Gensini score were significantly related to poor CCC. The rapid and cost-effective use of new inflammatory markers in clinical practice guides the prognosis of CAD.