Subclinical myocardial injury increases the risk of heart failure in patients with and without type 2 diabetes post-acute coronary syndrome

Background: Little is known about the effect of subclinical myocardial injury (sMi) on heart failure (HF) risk after acute coronary syndrome (ACS). We examined the frequency patterns of sMi after ACS among patients with and without diabetes mellitus (DM), and the influence of sMis on HF risk at 1 year. Methods: Fifty patients with ACS who underwent revascularization were prospectively enrolled. After discharge, serial study visits were conducted and high-sensitivity cardiac troponin T (hs-TnT) levels were checked at 3-month intervals for 1 year. sMi was defined as hs-TnT ≥14 ng/L without clinical symptoms. The primary endpoint was a composite of post-ACS chronic HF or significant left ventricular (LV) dysfunction without HF symptoms. A multivariable logistic regression model was used for risk evaluation. Results: The mean patient age was 58 years, and 90% were men. Overall, 44% of patients had DM, and the median LV ejection fraction at discharge was 56%. Patients with DM had a higher incidence of sMi than those without DM (63.6% vs. 32.1%, P < 0.05). sMi occurred at least twice in most patients, and the prevalence declined over time in DM, but not in non-DM. Fourteen patients (28%) met the primary endpoint at 1 year, and the risk was higher in patients with DM (odds ratio: 4.99) and patients with sMi (odds ratio: 6.26). However, sMi was not a mediator of the association between DM and HF risk. Conclusions: Patients with DM had a higher incidence of sMi. Nonetheless, sMi increased the risk of HF after ACS, irrespective of diabetes status.