Abstract: This study aims to analyze the factors associated with the lack of carbohydrate antigen 125 (CA-125) elevation in cases of acute heart failure (HF) decompensation. This retrospective study was conducted on 3167 consecutive patients admitted for acute HF in the cardiology department of a referral hospital (June 2019 to June 2024). Admissions from outpatient clinics (n: 1018) and transfers from other hospitals (n: 752) were excluded. The variables of interest included clinical, echocardiographic, therapeutic, and analytical factors. Low CA-125 levels were defined as values ? 50 U/mL. A total of 1397 patients were included, of whom 515 had normal CA-125 levels and 882 had elevated levels. Clinically, independent predictors of low CA-125 were sinus rhythm on electrocardiogram (OR: 1.42, 95% CI: 1.12-1.64; p: 0.003) and sleep apnea-hyponpnea syndrome (OR: 1.76, 95% CI: 1.15-2.70; p: 0.009). Echocardiographically, inferior vena cava collapse greater than 50% with inspiration was associated with low CA-125 (OR: 1.78, 95% CI: 1.19-2.69; p = 0.005), as well as with non-severe right ventricular dysfunction. (OR: 2.42; IC95%: 1.39-4.20; p: 0.002). Analytically, elevated NT-proBNP levels were associated with elevated CA-125 levels (OR: 0.99; IC95%: 0.99-0.99; p: 0.006). Survival was higher in the group with CA-125 ? 50 U/mL (p: 0.019). Conversely, as CA-125 values increased, mortality also rose. In conclusion, the absence of CA-125 elevation in patients admitted for acute HF is associated with sinus rhythm, sleep apnea-hyponpnea syndrome, low NT-proBNP levels, and inferior vena cava collapse greater than 50% with inspiration.
