Prevalence and Prognostic Implications of Atherosclerotic Coronary Artery Disease in Type 2 Myocardial Infarction.

BACKGROUND

Type 2 myocardial infarction (MI) (T2MI) is common and associated with adverse outcomes.

OBJECTIVES

The objective of the study was to evaluate the prevalence of coronary artery disease (CAD) in patients with T2MI and myocardial injury and its impact on outcomes.

METHODS

Observational U.S. cohort study of emergency department patients undergoing high-sensitivity cardiac troponin T measurement. Cases with >1 high-sensitivity cardiac troponin T increase >99th percentile were adjudicated following the Fourth Universal Definition of MI. CAD was defined as a prior CAD, MI, or coronary revascularization or newly diagnosed CAD during index hospitalization. Two-year major adverse cardiovascular outcomes including all-cause, cardiovascular, and noncardiovascular death, acute MI, heart failure hospitalization, and coronary revascularization were compared between patients with T2MI or myocardial injury and CAD vs type 1 MI (T1MI).

RESULTS

Among 858 patients, 64 (7.5%) had T1MI, 91 (11%) had T2MI, and 703 (82%) had myocardial injury. Patients with T2MI and CAD (n = 31; 34% of T2MI) had higher major adverse cardiovascular outcomes than T1MI (65% vs 39%; adjusted HR [aHR]: 1.95; 95% CI: 1.2-3.6), driven by higher all-cause death (52% vs 20%; aHR: 2.2; 95% CI: 1.0-4.5), noncardiovascular death (26% vs 5%; aHR: 5.04; 95% CI: 1.3-19.3), acute MI (13% vs 2%; aHR: 9.2; 95% CI: 1.01-84.2), and heart failure hospitalization (32% vs 8%; aHR: 4.6; 95% CI: 1.6-13.7). Patients with myocardial injury and CAD (n = 245) demonstrated similar trends, although differences were not statistically significant after adjustment.

CONCLUSIONS

CAD is common among patients with T2MI and myocardial injury and is associated with poor long-term outcomes. Its presence may facilitate risk-stratification and represent a potential therapeutic target.