Combined MIRACLE2 and CAHP Scores Enhance Mortality Prediction in Out-of-Hospital Cardiac Arrest With STEMI

Out-of-hospital cardiac arrest (OHCA) with ST-segment elevation myocardial infarction (STEMI) carries a high mortality risk. The MIRACLE2 and Cardiac Arrest Hospital Prognosis (CAHP) scores show promise for neurological outcome prediction, but their performance for in-hospital mortality in patients with OHCA-STEMI remains unclear.

Accurate early mortality prediction could guide decisions regarding percutaneous coronary intervention and resource allocation in high-risk patients with OHCA-STEMI.

We analyzed 120 patients with OHCA-STEMI (2019-2023), comparing MIRACLE2 and CAHP for mortality prediction. Both demonstrated excellent discrimination (MIRACLE2 0.855 vs CAHP AUC 0.878, P = 0.360). Missing data impacted performance, with CAHP more vulnerable than MIRACLE2. In combined modeling, CAHP retained independent significance while MIRACLE2 did not. Traditional cutoffs (MIRACLE2 ≥5, CAHP >200) had high specificity but poor sensitivity (<25%). Patients with either or both scores elevated by traditional cutoffs demonstrated >90% mortality. Derived cutoffs (MIRACLE2 ≥4, CAHP ≥158) improved sensitivity (MIRACLE2 75.9%, CAHP 81.0%).

MIRACLE2 and CAHP are strong predictors of mortality in OHCA-STEMI, and using both in parallel improves identification of patients unlikely to benefit from percutaneous coronary intervention.