Debate: Revascularization of non-culprit lesions in ACS: physiology, OCT-guided or both? Perspective from physiology

Answer: I would like to start by contextualizing the change of paradigm we’ve been experiencing regarding myocardial revascularization. In controlled clinical trials of stable coronary artery disease, compared to optimal medical therapy, unfortunately, myocardial revascularization—the percutaneous one (PCI) in particular—has not been able to reduce clinical events whether angiography-guided (COURAGE and BARI 2D trials) or guided by non-invasive ischemia detection studies (ISCHEMIA trial).1 1It is hard to believe that although there is a significant correlation between the degree of ischemia documented non-invasively and the risk of adverse events, revascularization based on the information that, as interventional cardiologists, we collecrt from non-invasive studies doesn’t lead to better clinical outcomes compared to non-revascularizing the patient leaving him with ischemia and on optimal medical therapy. Here’s where the use of the pressure guidewire (PG) during the procedure (and possibly its angiographic alternatives) seems to lead to a different outcome. Currently, 3 randomized clinical trials are being conducted—2 of them in patients with acute coronary syndrome (ACS)—comparing the clinical events associated with PGand optimal medical therapy-guided myocardial revascularization alone. A recent metanalysis revealed that, compared to optimal medical therapy, PG-guided myocardial revascularization reduces the risk of cardiac death an infarction significantly at 5 years.2 We should mention that this is a high-quality metanalysis that only included randomized clinical trials and «hard» events in its primary outcome. Also, unlike the ISCHEMIA trial that reported more early events associated with revascularization, fewer events were also documented in the PG arm from the beginning of follow-up and, as years went by, this event difference has grown favorable to revascularization. This and other information suggest that the PG allows us to select more accurately compared to angiography the segments of epicardial arteries where the benefits of PCI exceed risks.3,4 This evidence has changed the clinical practice guidelines that now recommend the use of the PG for the lack of previous evidence of ischemia and when the use of revascularization is under consideration. However, although this recommendation has been effective for years, the clinical use of PG is still low worldwide.