Comparative Short-Term Prognostic Discrimination of the 2026 AHA/ACC and 2019 ESC Risk Classifications in Hospitalized Acute Pulmonary Embolism: A Retrospective Two-Campus Cohort Study.
Abstract
Background
The 2026 American Heart Association/American College of Cardiology (AHA/ACC) and 2019 European Society of Cardiology (ESC) pulmonary embolism (PE) classifications represent severity differently: AHA/ACC spans subclinical PE through cardiopulmonary failure, whereas ESC defines high risk by hemodynamic instability. Their prognostic separation is uncertain. RESEARCH QUESTION How do these classifications compare in mortality discrimination and identification of patients at high observed risk in hospitalized acute PE? STUDY
Design
AND
Methods
We retrospectively studied 2,251 patients at a two-campus Chinese tertiary hospital (2013-2025). Index time was admission for community-acquired PE and symptom onset or first objective imaging for hospital-acquired PE. The primary outcome was 30-day all-cause mortality; institutionally determined PE-related mortality was post hoc. Paired DeLong tests compared ordinal areas under the receiver operating characteristic curves (AUCs), and AHA/ACC categories D-E defined the analysis high-risk threshold.
Results
127 patients (5.6%) died within 30 days and 80 (3.6%) had PE-related death. Thirty-day AUCs were 0.885 (95% confidence interval [CI], 0.858-0.912) for AHA/ACC and 0.763 (95% CI, 0.721-0.806) for ESC (difference, 0.122; 95% CI, 0.084-0.160; P < .001). PE-related mortality AUCs were 0.942 and 0.826, respectively (difference, 0.116; 95% CI, 0.068-0.164; P < .001). At the analysis-defined high-risk thresholds, sensitivities for PE-related death were 83.8% for AHA/ACC categories D-E and 58.8% for the ESC high-risk stratum, with specificities of 95.1% and 95.8%, respectively. Among 37 patients in AHA/ACC categories D-E but the ESC intermediate-risk stratum, 75.7% died by 30 days and 54.1% had PE-related death. Excluding AHA/ACC A and E attenuated the 30-day AUC difference to 0.112 (95% CI, 0.038-0.186).
Interpretation
Under inpatient care, the AHA/ACC categories showed greater full-spectrum ordinal separation and identified a phenotype with substantial observed mortality risk that was not classified as ESC high risk. Attenuation within the central severity range indicated that the difference was spectrum dependent. TAKE HOME POINTS Study Question:How do the 2026 AHA/ACC Acute PE Clinical Categories and the 2019 ESC scheme compare for short-term mortality prognosis in hospitalized acute PE?
Results
AHA/ACC showed greater full-spectrum ordinal separation for 30-day all-cause and institutionally determined PE-related mortality and identified an ESC intermediate-risk subgroup with high early mortality, although the difference attenuated when the AHA/ACC severity extremes were removed.
Interpretation
The findings suggest that broader severity phenotyping may identify clinically important discordance while remaining limited to prognostic performance under observed care.