Debate. Revascularization of nonculprit lesions in ACS: physiology or OCT-guided or both? Perspective from imaging

Answer: The publications of the COMPLETE and FLOWER MI clinical trials has changed the management of nonculprit lesions tremendously in patients with ACS jeopardizing the role of the pressure guidewire guiding the revascularization of these lesions.1,2 In the COMPLETE trial, angiography-guided complete revascularization reduced the rates of death and infarction compared to the optimal medical therapy (OMT).1 We should mention that over 80% of the lesions included had an angiographic percent diameter stenosis ≥ 70%.1 In the FLOWER MI trial that included less severe nonculprit lesions, pressure guidewire-guided complete revascularization reduced the number of lesions treated (45% fewer lesions) compared to angiography-guided complete revascularization with a similar rate of events in both strategies.2 However, a subanalysis of the group of patients treated with pressure guidewire guidance revealed that patients with fractional flow reserve (FFR) values ≤ 0.80 (stented according to protocol) had fewer events compared to patients with FFR values > 0.80 (treated with OMT).3 This has aroused controversy regarding the utility of the pressure guidewire in this context. Probably the reason why the FFR has such a low negative predictive value is the lack of information on the composition of the plaque of the target lesion. In a subanalysis of the COMPLETE trial where nonculprit lesions were treated with OCT, it was reported that > 35% of the lesions with stenosis ≥ 70% were classified as vulnerable plaques compared to 25% of intermediate lesions (stenosis between 50% and 69%).4