Background:

Shock index (SI), calculated as the ratio of heart rate (HR) to systolic blood pressure (SBP) obtained on admission, and age-adjusted SI are tools that have already demonstrated prognostic value in some clinical contexts, but their prognostic value in decompensated heart failure (DHF) is unknown.

Objective:

The aim of this study was to evaluate the prognostic ability of both indices for total in-hospital mortality in patients admitted to the coronary unit for DHF.

Methods:

We conducted a retrospective study of consecutive patients admitted to 2 coronary care units between January 2010 and August 2020. Both indices and their respective predictive values were calculated. The cutoff point values with the best combination of sensitivity and specificity were defined using the ROC curve. Multivariate analysis was performed to identify independent predictors of in-hospital mortality.

Results:

Population: 1472 patients. Median age was 81 years, 50 had left ventricular ejection fraction <40% and 50% had a history of DHF. In-hospital mortality 6.2%. Youden’s index identified SI ≥0.58 and age-adjusted SI ≥45.6 as predictors of mortality. On multivariate analysis including age, systolic blood pressure (SBP) <115 mmHg, blood urea nytrogen (BUN) >43 mg/ dL, creatinine level >2.75 mg/dL, hemoglobin (Hb) <10 g/dL and SI ≥0.58, only age, BUN >43 mg/dL and anemia remained as independent predictors of in-hospital mortality. On multivariate analysis, when age-adjusted SI ≥45.6 was analyzed with the other variables (but not with age), the independent predictors were age-adjusted SI ≥45.6 (OR 2.41; 95% CI, 1.37-4.2; p <0.01), BUN >43 mg/dL and anemia.

Conclusion:

A simple calculation as age-adjusted SI is highly useful to predict in-hospital mortality in patients hospitalized with DHF and provides additional information to the classic prognostic variables.