External prognostic validation of the EHMRG score for risk stratification and disposition decisions in acute heart failure

Risk stratification in patients with Acute Heart Failure (AHF) is critical for optimizing disposition decisions in the Emergency Department (ED). While clinical judgment is the cornerstone of management, “borderline” patients often present a challenge. The Emergency Heart Failure Mortality Risk Grade (EHMRG) score was developed to objectively predict short-term mortality. This study aims to prospectively validate the EHMRG score for predicting 30-day all-cause mortality and to evaluate its performance for 7-day mortality as a secondary outcome, as well as its concordance with clinician disposition decisions. This prospective, single-center, observational external prognostic validation study enrolled adult patients presenting to the ED with AHF between August 2022 and January 2023. The EHMRG score was calculated for all patients but blinded to treating physicians to prevent influence on decision-making. The primary outcome was 30-day all-cause mortality. Seven-day all-cause mortality was evaluated as a secondary outcome due to the limited number of early events. Discriminatory performance for short-term mortality was assessed using Receiver Operating Characteristic (ROC) curve analysis. A total of 237 patients were included (median age 76 years; 53.6% female). The overall mortality rate was 16.9% at 30 days and 5.9% at 7 days. The EHMRG score demonstrated moderate discriminative ability with an Area Under the Curve (AUC) of 0.755 (95% CI: 0.67–0.84) for 30-day mortality and 0.741 (95% CI: 0.61–0.87) for 7-day mortality. Notably, no deaths occurred in the very low- or low-risk groups (Negative Predictive Value > 97%). However, discordance was observed between clinical judgment and risk scores; 27% of patients were discharged despite being classified as moderate to very high risk by EHMRG. Notably, 12.5% of the 30-day non-survivors originated from this discharged group. The EHMRG score demonstrated acceptable discrimination for predicting 30-day mortality in this cohort of emergency department patients with acute heart failure. When used alongside clinical judgment, the score may assist clinicians in identifying patients who could potentially be considered for safe discharge. ClinicalTrials.gov, NCT05710302. Registered January 24, 2023.