Ischemia-guided vs routine non-culprit vessel percutaneous coronary intervention for patients with multi-vessel disease presenting with ST segment elevation myocardial infarction: the IAEA SPECT STEMI trial

Introduction: Efficacy and safety of ischemia-guided vs routine non-culprit vessel percutaneous coronary intervention (PCI) has not been adequately studied in patients with multi-vessel disease presenting with ST elevation myocardial infarction (STEMI).

Methods: An international, randomized, non-inferiority trial comparing ischemia-guided non-culprit vessel angioplasty to routine non-culprit vessel PCI, following primary PCI for STEMI was conducted in nine countries, sponsored by the International Atomic Energy Agency (IAEA). The primary outcome was the between-group difference in percent ischemic myocardium at follow-up stress SPECT myocardial perfusion imaging (MPI). All MPI images were processed and analyzed at a central core lab, blinded to treatment allocation.

Results: In all, 109 patients were included. In the ischemia-guided arm, 25/48 (47%) patients underwent non-culprit vessel PCI following stress MPI, while in the routine non-culprit PCI arm, 43/56 (77%) patients underwent PCI. The median percentage of ischemic myocardium on follow-up imaging (mean 16.5 months) was low, and identical (2.9%) in both arms (difference 0.13%, 95%CI 2 1.3%–1.6%, P < .0001; non-inferiority margin 5%).

Conclusions: A strategy of ischemia-guided non-culprit PCI resulted in low ischemia burden, being non-inferior to a strategy of routine non-culprit vessel PCI. In addition, a selective non-culprit PCI following STEMI offers the potential for cost-savings, and may be particularly relevant to low-and-middle income countries, where appropriate allocation of resources is critical.