Aims: The optimal timing of intervention in non-ST-elevation myocardial infarction (NSTEMI) remains uncertain. The aim of this multicentre trial was to assess whether an immediate invasive approach is superior to an early invasive or a selective invasive approach with respect to reduction of large infarction.
Methods and results: Patients with NSTEMI were randomized to either an immediate (<2 h after randomization; n= 201), an early (10-48 h after randomization; n= 200), or a selective invasive approach with high invasive percentage (n= 201). The primary outcome was the peak creatine kinase (CK)-myocardial band (MB) activity during index hospitalization; key secondary clinical endpoints were the composite of (i) death and non-fatal infarction; (ii) death, non-fatal infarction, and refractory ischaemia; (iii) death, non-fatal infarction, refractory ischaemia, and rehospitalization for unstable angina within 6 months. The median time from randomization to angiography was 1.1 h in the immediate vs. 18.6 h in the early and 67.2 h in the selective invasive group (P< 0.001). There was no significant difference in the peak CK-MB activity between groups. The key secondary clinical endpoints were similar between groups at 6-month follow-up: death and infarction: 21.0 vs. 16.0 vs. 14.5%; P= 0.17; death, infarction, refractory ischaemia: 20.9 vs. 21.5 vs. 22.0%; P= 0.98; death, infarction, refractory ischaemia, rehospitalization: 26.0 vs. 26.5 vs. 24.5%; P= 0.91, respectively.
Conclusions: In NSTEMI patients, an immediate invasive approach does not offer an advantage over an early or a selective invasive approach with respect to large myocardial infarctions as defined by peak CK-MB levels, which is supported by similar clinical outcomes. ClinicalTrials.gov NCT00402675.