Serum NT-ProBNP/Chloride Ratio Predicts Adverse Cardiovascular Outcomes in Patients with Acute Heart Failure

Background: Heart failure (HF) is a public health issue. It represents the second most common cause of hospitalization and the leading cause in individuals over 60 years old. Tools that predict adverse outcomes in patients with HF are needed. Objective: This study analyzed the prognostic role of the serum NT-proBNP/chloride ratio as a predictor of major cardiovascular events in patients with acute decompensated HF. Methods: Patients with a confirmed diagnosis of acute decompensated heart failure were retrospectively enrolled in the study; admission NT-proBNP/chloride ratio was used to stratify patients above or below the median (>/<83). The primary composite endpoint consisted of cardiovascular mortality, decompensated HF readmission, and unplanned emergency department visits. Results: A total of 197 individuals were included, of whom 100 (50.7%) were classified above and 97 (49.2%) below the median. Patients showing a high ratio had a lower LVEF (31 vs. 39%), a higher proportion of previous MI (30 vs. 15%), a lower diastolic blood pressure (73 vs. 80 mmHg), and higher BUN (38 vs. 23 mg/dL) and creatinine (1.6 vs. 1.1 mg/dL). After a follow-up period of 92 ± 3 days, 46 patients (23%) presented the primary endpoint; those with a high NT-proBNP/chloride ratio showed an increased risk (HR 3.18, 95% CI 1.55-6.52, p = 0.0015) of the primary endpoint. After multivariate analysis, only serum NT-proBNP/chloride ratio (p = 0.02) and diastolic pressure (0.037) remained significant. The area under the ROC curve for the NT-proBNP/chloride ratio for predicting the primary composite endpoint was significantly superior when compared with AUC for NT-proBNP or chloride alone. Conclusions: The serum NT-proBNP/chloride ratio is a novel, easy to use predictor of short- and medium-term cardiovascular events in patients with acute decompensated HF.