Treatment of myocardial infarction (MI) differs based on MI type, which can be difficult to determine in the emergency department. This study sought to evaluate whether a machine learning algorithm (MI ³ ) in combination with N-Terminal pro B-type natriuretic peptide (NT-proBNP) and galectin-3 (Gal-3) can accurately differentiate MI type.

We conducted a secondary analysis of the multisite CMR-IMPACT trial, which prospectively enrolled adults with symptoms of acute coronary syndrome and an initial indeterminate troponin. Patients with an adjudicated diagnosis of MI and an initial high-sensitivity cardiac troponin I (hs-cTnI; Abbott Laboratories) measure were included. Incidence of MI and MI type were adjudicated by expert reviewers. Receiver operator characteristic curves for MI-type were created and area under the curve (AUC) calculated for MI ³ and MI ³ with NT-proBNP and Gal-3. AUCs were compared using DeLong’s method.

Among 123 patients with adjudicated MI, the mean age was 60±12 years and 37.4% (46/123) were female. Type 1 MI occurred in 58.5% (72/123) and type 2 MI in 41.5% (51/123). MI ³ based on an initial hs-cTnI yielded an AUC of 0.704 (95% CI 0.611-0.797) for MI type. When combined with NT-proBNP and Gal-3, AUC improved to 0.789 (95% CI 0.709-0.869, p =0.0165). In patients with serial hs-cTnIs ( n = 86), the AUC of MI ³ for MI type was 0.721 (95% CI 0.614-0.829) and increased to 0.797 (95% CI 0.700-0.894, p =0.09) with the addition of NT-proBNP and Gal-3.

Adding NT-proBNP and Gal-3 to the MI ³ machine learning algorithm shows promise in differentiating type 1 from type 2 MI.