Introduction: Development of heart failure is a frequent complication following ST-elevation myocardial infarction (STEMI), even in younger patients with coronary artery disease (CAD). Aim of the present study was to analyze the impact of diabetes mellitus on the development of heart failure in young patients with STEMI.

Methods: All patients with STEMI ≤45 years old, that were treated with emergency percutaneous coronary interventions (PCI) at a large German heart centre between 2015 and 2017, entered analysis. Follow-up examination, including echocardiography, determination of NT-pro-BNP and assessment of clinical events, was performed after 1 and 5 years.

Results: Out of n=145 patients included in this study, 129 were males (89%) and 16 females (11%). 6 patients (4%) had known diabetes and 24 patients (17%) were newly diagnosed, while 115 (79%) did not have diabetes. At index event patients with diabetes were more likely to have a reduced LV-EF (<50%): 43% vs. 26%, p<0.01. This difference increased over time (5 yrs: 47% in diabetics vs. 15% in non-diabetics, p<0.01). While in non-diabetics the LV-EF improved to nearly normal levels in a large proportion of patients over time (p=0.05, table, left side), this improvement could not be observed in diabetics (p=0.98, table, right side). At the same time NT-pro-BNP remained high in 19% of patients with diabetes mellitus, while in non-diabetics it was no more detectable after 5 years (table). A multivariate analysis, adjusted for age and gender, revealed a trend towards reduced LV-EF in young patients with diabetes at the index event (OR 2.4, 95% CI 0.9-6.3, p=0.07); this disadvantage for diabetics incremented after 5 years (OR 8.3, 95% CI 0.9-36.4, p<0.01). While rates of unplanned (emergency) PCI during follow-up were higher in diabetics compared to non-diabetics (37% vs. 27%), this difference failed to reach statistical significance (p=0.39).

Table 1: Long-term follow-up, focusing on heart failure, in young diabetic vs. non-diabetic patients with STEMI