Biomed Pap Med Fac Univ Palacky Olomouc Czech Repub. X:X | DOI: 10.5507/bp.2026.010

The association between C-reactive protein/albumin ratio and coronary collateral circulation in patients with chronic coronary syndromes and chronic total occlusion

Sinan Iscen¹, Veysel Ozan Tanik¹, Cagatay Tunca¹, Suleyman Kayisoglu¹, Kursat Akbuga¹, Bulent Ozlek²

¹ Department of Cardiology, Ankara Etlik City Hospital, Ankara, Turkey

² Department of Cardiology, Faculty of Medicine, Mugla Sitki Kocman University, Mugla, Turkey

Background: The C-reactive protein-to-albumin ratio (CAR) has recently gained attention as a novel biomarker reflecting both systemic inflammation and nutritional status. Since inflammation plays a critical role in the formation of the coronary collateral circulation (CCC), this study aimed to investigate the association between CAR and the extent of CCC in patients with chronic coronary syndromes (CCS) and chronic total occlusion (CTO).

Methods: A total of 123 consecutive patients with CCS and angiographically documented CTO were included. CCC was assessed using the Rentrop classification and patients were divided into two groups: poor CCC (grades 0-1) and good CCC (grades 2-3). Laboratory data including C-reactive protein (CRP), albumin, lipid parameters, renal and liver function tests, glucose, and complete blood count were recorded. CAR was calculated by dividing CRP (mg/L) by albu­min (g/dL), and neutrophil-to-lymphocyte ratio (NLR) was also evaluated.

Results: Patients with poor CCC had significantly higher CRP, CAR, and NLR levels (P<0.05 for all). In multivariate logistic regression, both CAR (OR=1.200, 95% CI: 1.102-1.394, P<0.001) and NLR were independently associated with poor CCC. ROC analysis showed that CAR had better predictive value (AUC=0.79) than CRP (AUC=0.75, P=0.02) and NLR (AUC=0.67, P=0.03). A CAR cutoff of 2.36 yielded 67% sensitivity and 68% specificity.

Conclusion: Elevated CAR is independently associated with impaired CCC in patients with CCS and CTO. CAR may serve as a simple and superior marker over traditional inflammatory indices in assessing collateral vessel development.

Keywords: C-reactive protein (CRP), albumin, CRP/albumin ratio (CAR), coronary collateral circulation (CCC), inflammation, chronic coronary syndromes (CCS)

Received: July 15, 2025; Revised: January 29, 2026; Accepted: March 30, 2026; Prepublished online: April 16, 2026