Prognostic Value of the C-Reactive Protein-to-Albumin Ratio in Patients Hospitalized with Atrioventricular Block: Association with In-Hospital Mortality and Temporary Pacemaker Requirement

Background and Objectives: The C-reactive protein-to-albumin ratio (CAR) is an available marker of inflammatory–nutritional vulnerability, but its prognostic value in atrioventricular (AV) block is unclear. We investigated whether CAR is associated with in-hospital mortality and temporary pacemaker requirement (TPR) in hospitalized AV block. Materials and Methods: The study included 698 adults hospitalized with second-degree or higher AV block between January 2012 and July 2020. CAR was calculated from admission C-reactive protein and albumin levels. The primary endpoint was in-hospital mortality, and the secondary endpoint was TPR. Results: In-hospital mortality occurred in 14.5% of patients, and TPR occurred in 33.7%. CAR was higher in non-survivors than survivors (0.51 [0.13–1.85] vs. 0.13 [0.05–0.45], p < 0.001) and in patients with TPR than those without TPR (0.29 [0.09–1.10] vs. 0.13 [0.05–0.41], p < 0.001). Mortality increased across CAR quartiles from 3.8% to 27.7%, and TPR increased from 19.7% to 48.0%. In adjusted models, ln(1 + CAR) was independently associated with mortality (OR 2.14, 95% CI 1.44–3.19; p < 0.001) and TPR (OR 1.99, 95% CI 1.38–2.86; p < 0.001). Adding CAR modestly improved discrimination for mortality (0.751 to 0.782; p = 0.020) and TPR (0.623 to 0.671; p < 0.001), without clear superiority over its individual components. Conclusions: CAR was independently associated with in-hospital mortality and TPR in hospitalized AV block.