Immediate or Deferred Nonculprit-Lesion PCI in Myocardial Infarction.

BACKGROUND

The preferred timing of treatment of nonculprit lesions in patients with ST-segment elevation myocardial infarction (STEMI) remains uncertain. A comparison of immediate percutaneous coronary intervention (PCI) guided by instantaneous wave-free ratio (iFR) and deferred PCI guided by cardiac stress magnetic resonance imaging (MRI) in patients with STEMI and multivessel disease is warranted.

METHODS

In this international, investigator-initiated, open-label, randomized, controlled trial, patients with STEMI and at least one nonculprit lesion who had undergone successful primary PCI were randomly assigned in a 1:1 ratio to immediate iFR-guided PCI (in lesions with >50% stenosis and an iFR of ≤0.89 [normal value, >0.89]) or deferred cardiac stress MRI-guided PCI within 6 weeks after randomization. The primary end point was a composite of death from any cause, recurrent myocardial infarction, or hospitalization for heart failure at 3-year follow-up.

RESULTS

The trial included 1146 patients (558 in the iFR group and 588 in the MRI group) with a mean (±SD) age of 63±11 years; 78% were men. A total of 237 of 556 patients (42.6%) in the iFR group and 110 of 587 patients (18.7%) in the MRI group underwent nonculprit-lesion coronary-artery PCI. A primary-end-point event occurred in 50 patients (9.3%) in the iFR group and in 55 patients (9.8%) in the MRI group (hazard ratio, 0.95; 95% confidence interval, 0.65 to 1.40; P = 0.81). Serious adverse events occurred in 145 patients in the iFR group and in 181 in the MRI group.

CONCLUSIONS

Among patients with STEMI who have undergone successful primary PCI, immediate iFR-guided PCI was not superior to deferred cardiac stress MRI-guided PCI of nonculprit coronary-artery lesions with respect to death from any cause, recurrent myocardial infarction, or hospitalization for heart failure at 3 years. (Funded by Philips Volcano and others; iMODERN ClinicalTrials.gov number, NCT03298659.).