Abstract

**Background and aim:** Previous studies found conflicting results on the effects of earlier invasive intervention in a heterogeneous population of acute non-ST elevation myocardial infarction (NSTEMI) (1). Our aim was to explore in-hospital and 1-year follow-up outcomes in NSTEMI patients (pts) treated with PCI in the first 24 h, PCI after 24 h and optimal medical therapy (OMT). **Patients and Methods:** From January 2012 to October 2017, 1898 pts were enrolled in the Croatian arm of the ISACS-CT registry (NCT01218776) 36% (n=685) with NSTEMI, of which 675 had available data on treatment modality. One-year follow-up was available in 217 (32%) of the NSTEMI patients. **Results:** In 57% (n=386) of pts PCI was done within 24 h from symptoms onset, in 14% (n=95) after 24 h, while 29% (n=194) were discharged with OMT. Pts in the OMT group were significantly older, with more comorbidities, with a lower left ventricular ejection fraction (LVEF) value at discharge and greater delay from symptom onset to hospitalization (**Table 1**). Pts with PCI performed within 24 h had the greatest frequency of PCI reintervention during follow-up (PCI ≤ 24 h; PCI > 24 h; OMT: 15%; 3%; 0%; p=0.008). In-hospital mortality did not significantly differ between the groups (PCI ≤ 24 h; PCI > 24 h; OMT: 2.5%; 3.5%; 4.6%; p=0.220), yet in those with data on 1-year mortality (**Figure 1**), this was the highest in the OMT group (PCI ≤ 24 h; PCI > 24 h; OMT: 3.3%; 8.3%; 19.4%; p=0.005). Univariable regression suggested that PCI 25, P75) kg/m2 | 28.7 (26.1, 31.9) | 28.6 (25.6, 32.6) | 27.7 (25.1, 31.1) | 0.183 | | Beta-blockers before initial admission, n (%) | 150 (39) | 37 (40) | 90 (52) | **0.013** | | Diuretics before initial admission, n (%) | 116 (30) | 42 (45) | 94 (49) | **25, P75) µmol/L | 94 (80, 109) | 90 (77, 114) | 103 (85, 128) | **25, P75), days | 5 (4,8) | 5 (4, 9) | 8 (6,11) | **<0.001** | [†] PCI – percutaneous coronary intervention, OMT – optimal medical therapy, BMI – body mass index, EF – left ventricular ejection fraction, SD – standard deviation, P – percentile, h – hours. FIGURE 1. Patient survival. OMT – optimal medical therapy, PCI – percutaneous coronary intervention. **Conclusion:** NSTEMI patients in the three treatment groups had different risk profiles at hospitalization, the OMT group being burdened with most comorbidities. The therapy of choice did not seem to have a significant influence on in-hospital or 1-year survival. Due to their higher risk profile, the pts treated with OMT had significantly lower 1-year survival, with lower LVEF and higher rate of CKD as predictors of primary outcome.

Keywords

acute coronary syndrome, percutaneous coronary intervention

DOI

Literature

1. Milosevic A, Vasiljevic-Pokrajcic Z, Milasinovic D, Marinkovic J, Vukcevic V, Stefanovic B, et al. Immediate Versus Delayed Invasive Intervention for Non-STEMI Patients: The RIDDLE-NSTEMI Study. JACC Cardiovasc Interv. 2016 Mar 28;9(6):541–9. https://doi.org/10.1016/j.jcin.2015.11.018