Concordance Between E/e’ Ratio and N-Terminal Pro-B-type Natriuretic Peptide Levels for Predicting Post-Discharge Heart Failure Events Within Ninety Days After Acute Coronary Syndrome

Background: Heart failure (HF) is a common complication after acute coronary syndrome (ACS) and is linked to substantial morbidity and mortality. Both the E/e’ ratio and N-terminal pro-B-type natriuretic peptide (NT-proBNP) are widely utilized as noninvasive signs of cardiac filling pressure and hemodynamic stress. This study aimed to determine whether concordance between the E/e’ ratio and NT-proBNP level was associated with post-discharge HF events within 90 days among patients hospitalized with ACS. Methods: The current retrospective cohort study included 195 adults with ACS admitted to a military and teaching hospital for the Royal Thai Army between July 1, 2021, and August 31, 2025. Patients were sorted into three groups according to the concordance of the E/e’ ratio and age-specific NT-proBNP thresholds: concordantly low, discordant, and concordantly high. The primary outcome was a post-discharge HF event within 90 days after discharge, defined as an outpatient or emergency visit requiring diuretic therapy or hospitalization for HF. Time-to-event analyses were done using Kaplan–Meier methods and Cox proportional hazards regression. Results: Of the 195 patients, 34 (17.4%) were in the concordantly low group, 69 (35.4%) in the discordant group, and 92 (47.2%) in the concordantly high group. Post-discharge HF events within 90 days occurred in 33 patients (16.9%). Event rates were 0.68, 1.64, and 3.21 per 1,000 person-days in the concordantly low, discordant, and concordantly high groups, respectively. Compared with the concordantly low group, the concordantly high group had a significantly higher risk of the primary outcome in univariable analysis (hazard ratio (HR): 4.50; 95% confidence interval (CI), 1.06–19.14; P = 0.042) and in the reported multivariable model (adjusted HR: 5.97; 95% CI, 1.22–29.10; P = 0.027). The discordant group did not have a statistically significant increase in risk. Conclusions: Concordant elevation of the E/e’ ratio and NT-proBNP identified patients with ACS at substantially higher risk of post-discharge HF events within 90 days. Concordant elevation of E/e’ and NT-proBNP was associated with a higher rate of post-discharge HF events within 90 days after ACS. These exploratory findings require validation in larger prospective multicenter studies.