Aims: Treatment of the infarct-related artery only (IRA only) in ST-segment elevation myocardial infarction (STEMI) is associated with a significantly higher rate of ischaemia-driven revascularisation (ID-RV) during follow-up than fractional flow reserve-guided complete revascularisation (FFR-CRV). This study aimed to characterise all lesions which underwent ID-RV in the DANAMI-3-PRIMULTI trial with respect to location, stenosis grade and functional significance.
Methods and results: The study included 627 patients with STEMI and multivessel disease; 313 patients were randomised to treatment of the IRA only versus 314 undergoing staged FFR-CRV during the index admission. Rates of admission for suspected cardiac ischaemia (17%) were similar in both groups; however, ID-RV was significantly less frequent in the FFR-CRV group than in the IRA-only group (5% vs. 17%; p<0.001). In both groups, the primary reason for ID-RV was related to non-culprit, non-treated lesions (N=71/82 lesions in IRA-only; N=13/26 in FFR-CRV). De novo lesions or revascularisation of previously treated lesions were rarely causes of ID-RV. In the IRA-only group, there was a trend towards a higher ID-RV rate for lesions with a higher stenosis grade and located in more proximal segments - in particular, ≥80% stenosis of the left anterior descending and right coronary artery also led to angina class IV/unstable angina. In the FFR-CRV group, an FFR value ≤0.80 was shown to be an appropriate threshold for revascularisation.
Conclusions: FFR-CRV in STEMI is associated with a significantly lower rate of ID-RV at follow-up than treatment of the IRA only. This is due to a difference in non-culprit, non-treated lesions between both groups and not in de novo lesions or repeat revascularisation of previously treated lesions. Further considerations are warranted in case of high-grade non-culprit stenosis at proximal coronary segments, borderline FFR values and/or anticipated complex PCI.